In what year did the winter X games start requiring that all com Patores wear helmets 2011 2010 2009 2008

Answers

Answer 1

Answer:

The X games start requiring that all com Patores wear helemts in 2009..

Explanation:


Related Questions

what are some promo codes

Answers

Answer:

What do you mean by promo codes?????

Explanation:

For what store or site exactly?

Btw go download honey for all promocodes.

Answer:

they are alphanumeric stings that online stores offer to purchase on their website and thry typically have a promotional marking strategy

Explanation:

The dictionary and a helpful teacher taught me this

Correcting run-On sentences using semicolons
1 The economic summit meeting was held in Britain many diplomats attended.
2 I especially enjoy poetry by Emily Dickinson her poems are intense, concise, and revealing.
3 The use and abuse of drugs is a popular course because the material is geared for non-science majors.
4 The food festival offers a wide selection of food everything from hot dogs to elegant deserts was available.
5 Since the flight was turbulent, the flight attendant suggested that we remain in our seats.
6 The bowling alley was not crowded most of the lanes were open.
7 swimming is an excellent form of exercise it gives you a good aerobic workout.
8 When the disabled aircraft landed safely, the onlookers cheered.
9 The two-lane highway is being expanded to four lanes even that improvement is not expected to solve the traffic congestion problems.
10 Before visiting Israel, Carolyn read several guidebooks they helped her plan her trip.

Answers

Answer:

1. The economic summit meeting was held in Britain; many diplomats attended.

2. I especially enjoy poetry by Emily Dickinson; her poems are intense, concise, and revealing.

3. The use and abuse of drugs is a popular course, because the material is geared for non-science majors.

4. The food festival offers a wide selection of food; everything from hot dogs to elegant deserts was available.

5. Since the flight was turbulent, the flight attendant suggested that we remain in our seats.

6. The bowling alley was not crowded; most of the lanes were open.

7. Swimming is an excellent form of exercise; it gives you a good aerobic workout.

8. When the disabled aircraft landed safely, the onlookers cheered.

9. The two-lane highway is being expanded to four lanes; even that improvement is not expected to solve the traffic congestion problems.

10. Before visiting Israel, Carolyn read several guidebooks they helped her plan her trip.

Explanation:

Run-on sentences are sentences that consist of two or more independent clauses that are connected incorrectly. A common example of a run-on sentence is a comma splice, which occurs when independent clauses are connected just by a comma.

Run-on sentences can be corrected by adding a:

semicoloncomma followed by a subordinate conjunctioncomma followed by a coordinating conjunction

Run-on sentences can also be corrected by dividing the independent clauses into separate sentences.

Examples of run-on sentences are the first, second, fourth, sixth, seventh, and ninth sentences, and they are now corrected by adding the semicolon.

1) In line 7, the word “knell” most nearly means...

A. The past tense of kneel
B. The sound of ringing bells
C. A song
D. A type of se animal

2) This poem can be best describes as

A. Celebratory
B. Elegiac
C. Humorous
D. Persuasive

4) The topic of this poem can be best described as

A. The difficulty of continuing life after death
B. The transformative nature of death
C. the just death of the villain
D. Man’s return to the heaven after death

5) In line five, the word “suffer” most nearly means

A. To experience pain
B. To undergo
C. To die
D. To patiently endure

Answers

Answer:

No. 1: B. The sound of ringing bells

No. 2: B. Elegiac

No. 4: B. The transformative nature of death.

No. 5: B. To undergo

Explanation:

The poem is elegiac. It sounds sad and seems to talk about the transformative nature of death. The poem seems to explain what happens to the father that was in the grave.

Also, the sound of the knell in the poem depicts that it is elegiac.

Handle with Care——glassware inside

Answers

Answer:

fragile

Explanation:

Answer is - fragile

hope it helps

Please help me get this chart filled out

Answers

take a better picture

What is the best definition of the word pall as used in this sentence?

Her audience's attention began to pall as Catherine's speech kept going and going.


dwindle

culminate

wax

heighten

Answers

Answer:

Dwindle

Explanation:

Answer:

Dwindle

Explanation:


Why should a reader recognize the author's purpose?
A. It guides the respons of the reader.
B. It helps the reader honor the author's name.
C. It makes the reader agree with the author
OD. It encourages the author to write more.

Answers

Answer:

A. It guides the response of the reader

Explanation:

To recognize the authors purpose, it helps the response of the reader to better understand why they wrote what they did. Hope this helps

How does Anne Frank directly acknowledge conflicting viewpoints in her diary in Anne Frank: The Diary of a Young Girl?

(A) She writes why she thinks people should believe what she does.

(b) She quotes her family's conversations and explains how she disagrees.

(c) She describes and interprets other people's facial expressions.

(d) She guesses what her family members are thinking when they don't respond.

Answers

Answer:

B.

Explanation:

I took the test and that was the answer.

Answer: I think its b I hope this was helpful :D

Explanation:


We must do something to help the bee population win the battle against a colony collapse or the world faces horrendous consequences. Bees are important to our food chain. The loss of bees would mean the extinction of food as we know it.

What is the purpose of this passage?

Answers

Answer:

To inform and persuade the reader

Explanation:

Bees truly are essential to all life on Earth; without them there would be know pollination- with no pollination, there’s no flowers- without producers, the world dies. We need to keep their population safe.

Answer:

The awnser is persuasise.

We must do something to help the bee population win the battle against a colony collapse or the world faces horrendous consequences. Bees are important to our food chain. The loss of bees would mean the extinction of food as we know it.

What is the purpose of this passage?

The awnser is persuasise.  

:)

Explanation: thank you

Which sentence has the MOST objective tone?
The Northeast has at least five months of cold weather, which is four months too
many.
O We have a long, dreary wait until the beginning of spring.
O I can't agree with the poet that April is a cruel month.
O The northern United States is statistically colder for longer than the South.

Answers

it would be “the northern United States is statistically colder for longer than the south”. Objective means to have no bias, and this answer is the only one that uses statistics and not opinions

Answer: The northern United States is statistically colder for longer than the South.  

Explanation: This is the only sentence that sticks to facts and neutral language in describing the weather.

In the song, "And American Draft Dodger in Thunder Bay," does the phrase,
"Canadian Shield" have a double meaning?

Answers

Answer:

no it does not for your quistion

identify the figurative language in the following sentence "he did not live in a tenement but in a big white birthday cake of a house on laurel street" (page 230)

Answers

Answer:

big white i think im not sure tho

Explanation:

21
Select the correct answer.
Which citation style is used in literature?
ОА.
APA
OB.
AMA
Ос.
Chicago
OD.
MLA

Answers

MLA is most often used in literature

Answer:

MLA

Explanation:

Most common one

SPENCER, North Carolina (Achieve3000, May 17, 2019). Don't ever let anyone tell you that young people can't do great things. Take it from Mrs. Fleming's 7th-grade class at North Rowan Middle School in North Carolina. This compassionate classroom crew is proof-positive that young people can make a difference in the lives of others. And activism can begin with four little words: How can we help?

So how do you go from sitting in a classroom to tackling the problems of the world? For Mrs. Fleming's class, it all started with learning about horrible global events that devastate individuals, families, and communities.

"We planned a trip to Washington, D.C., so that we could immerse ourselves in learning about the Holocaust and refugees," said Mrs. Fleming. "We [also] had the opportunity to participate in a Doctors Without Borders interactive refugee exhibit. We read Achieve3000 articles and novels about refugees, and we watched documentaries and news clips."

Then, the students had yet another extraordinary experience: the chance to speak via video teleconference to a refugee named Lubo, one of the estimated 20,000 Lost Boys who found themselves displaced or orphaned during a deadly civil war that began in Sudan in the 1980s. The students were very moved by Lubo's story as he told them about what he witnessed before he fled Sudan.

"The enemy from the North attacked, people were caught, houses burned, nothing [was] left," student Katie P. remembered him saying. "[It was] really sad because all he had and everything he lived for was no longer there, no one to count on, nothing."

"[We realized that] we usually took everything for granted," said Katie's classmate, Jennifer G. "We never appreciated what we had."

It's one thing to read about history, and quite another to hear from someone who lived it, and who made it clear that Sudan is still affected by life-threatening issues like poverty and lack of access to clean water. The students knew they had to do something, and that's when they asked: "How can we help?"

Soon, they found their answer.

The class was invited by the nonprofit group Mothering Across Continents to host a Walk for Wisdom walkathon to raise money and awareness for impoverished schools in South Sudan. It was a great idea—but the students wanted to take it further.

"We said 'yes,' but asked if we could involve our whole community," Mrs. Fleming said. She joined forces with Karen Puckett, a media specialist at Isenberg Elementary School in Salisbury, North Carolina, which had participated in a school-based Walk for Wisdom for several years.

Meanwhile, the students in Mrs. Fleming's class leaped into action, working in teams to design t-shirts and flyers for the April 2019 walkathon. They also created an iMovie, a website, and a GoFundMe page to help raise money.

Even after all that, the students were just getting started! They planned a Refugee Awareness Community Night at their local bookstore, where they spoke to Ngor Kur Mayol—another Sudanese refugee. The event featured their presentations, art, and writing, as well as a marketplace to raise money for a source of clean water for the students at Nyarweng Primary School in South Sudan.

Mrs. Fleming and her students hope they will eventually be able to exchange messages and photos with the Nyarweng Primary School pupils.

All this might be just the beginning of an ongoing effort. "Our hope is that these events will turn into yearly global events for our county, and that our community will unite for a global cause to help youth in another country," Mrs. Fleming explained.

Needless to say, Mrs. Fleming is extremely proud of how her class has stepped up to help—not that she's surprised.

"Our students have incredible ideas," she said. "All we need to do is listen and encourage. I love seeing where my students' voices and actions can lead us."

And if you want to make a difference in the lives of others, student Kimberly F. has some advice.

"You may think that starting a project to change the world would be difficult," she said. "But if you really put your mind into it, you can achieve amazing things. It can start with a simple act in your community, but you'll see that it will grow and grow."

Most importantly, the students say, don't ever feel like you're too young to make a mark on the world.

"There are many things we are limited to do because we are kids," Katie said. "A lot of people may underestimate [us], but that is what drives us to stand out and help other people."


The best alternate headline for this Article would be __________.

A.Mothering Across Continents Arranges Walk for Wisdom Walkathons

B.Middle School Class Creates GoFundMe Page To Raise Money

C.Students Use Achieve3000 Articles To Learn About Tragic World Events

D.Students Tackle Global Problems One "Step" at a Time

Answers

Answer:

uh what is this basically asking

Explanation:

What is the question

Analyzing Exposition
bd
Why then do we continue in this miserable condition?
Because nearly the whole of the produce of our labour is
stolen from us by human beings. There, comrades, is the
answer to all our problems. It is summed up in a single
word-Man. Man is the only real enemy we have. Remove
Man from the scene, and the root cause of hunger and
overwork is abolished for ever.
-Animal Farm,
Why is this passage an example of exposition?
O It introduces one of the main conflicts of the novel.
It introduces several main characters in the novel.
O It describes the physical environment of the novel.
It describes the time period in which the novel takes
place.
George Orwell

Answers

Answer: A

Explanation:

Read the excerpt from "Ellis Island."

For 62 years, some 12 million people passed through Ellis Island for the promise of a better life in America. They came on huge steamships, the majority from Eastern Europe and Italy, the rest from other corners of the world: Lebanon, Cyprus, China, Jamaica, and numerous other places. Many had left their homelands to escape poverty, while others had fled religious persecution or war.

Which words signal the passage of time?

some 12 million people
fled religious persecution
through Ellis Island
For 62 years

Answers

Answer:

the answer is For 62 years

Explanation:

i took the test

Answer:

the awnser is d.for 62 years

Explanation:

i just took the test

The insidious burglar was able to sneak into the house without being heard or seen

Explain the word insidious
A strong
B loud
C clumsy
D sneaky

Answers

Answer:

sneaky

Explanation:

A-strong
Because insidious is a pressure of modern therefore it’s strong

The person with whom you find yourself identifying in a story sometimes depends on your own identity. With whom did you identify at the start of staples essay and how did it affect your reading of the full piece?

Answers

Answer:

As a woman, identifying with the story´s protagonist based on the first paragraph was complex. The beginning ('My first victim was a woman') made me feel like he was dangerous for those of my gender.

Explanation:

However, realizing that the 'victim' was actually a white woman discriminating against him for his race, something I have experienced personally because of my Latinamerican heritage, allowed me to identify myself with the protagonist, and therefore, I felt so much more immersed in his story.

S
1. a_hl___S it is in olympic​

Answers

Answer:

thx for the points

Explanation:

please help me asap​

Answers

C trust me thank me later

Answer: C.

Explanation:

Someone deleted my answer..

Hope this helps. Have a good night ma´ám/sir. Be safe!

Which consumers in the prairie ecosystem do you think are secondary consumers?

Answers

Answer:The Primary Consumers – the prairie dogs, grasshoppers, jackrabbits, and pronghorn antelope. The Secondary Consumers – the owls, rattlesnakes and coyotes. The Scavengers – the coyotes and insects.

Explanation:

write an informative essay on the topic of immigration. Your essay will use to research to describe the changes and challenges that today's immigrant children experience ​

Answers

Answer:

Those children get poor support from government agencies and face high level of discrimination.

Explanation:

Parents who have low levels of education and are poor have been subject to high levels of discrimination which in turn harms children. Those children get poor support from government agencies and face a high level of discrimination. They are racially classified as black or brown. This further makes the process of their settlement difficult.

Answer:

The immigrant children get poor support form government agencies and face high level of discrimination.Parents who have levels of education and poor have been subject to high levels of discrimination which in turn harm children. The immigrant children are racially classified as black or brown. This further makes the process of their settlement difficult. Immigration is used to keep people safe everywhere all though it sounds racist people still have to go through it. It is very hard to get by. Most people don't last it. 

Explanation:

e

NEED ANSWERS ASAP
(Score for Question 2: of 20 points)
Read the passage. Then answer the question.
Out of Place
“Ben bunu yapmayacağım . . . I will not do that. He can’t have my shoes, he stole my guitar!” Erkan’s eyes looked impudent beneath his dark brow as his cheeks reddened in fury. His gray-whiskered lips trembled as his hand gripped tightly around the nurse’s wrist. The nurse carefully but firmly freed himself from Erkan’s grasp. He then turned to the caregiver who was assisting him, smiled, and said calmly, “Go get Michelle.”
Michelle was scanning boxes of gauze bandages and stacking them onto a shelf in the storeroom when the caregiver came in and announced, “Phillip’s trying to get Erkan to take a shower and he needs your help.” Michelle rushed out of the store room and down the hall to Erkan’s room.
This was the last week of Michelle’s internship. It was her junior year, and the internship was part of her “Workplace and Consumer Education” class. At first she wanted to intern at her dad’s gas station, but her teacher told her she needed to branch out and signed Michelle up at the Oakcourt Nursing Home, only 15 minutes away from her house.
Wearing a Pittsburgh Steelers sweatshirt and jeans, with dark curls pushed back in a hair clip, Michelle stood out from the crowd of nurses and caregivers in white pants and polo shirts who were standing huddled in the doorway of Erkan’s room. She moved past them and rushed to Erkan’s side. As soon as he saw her, Erkan’s face brightened and he stopped looking like a stricken animal and instead looked like someone who recognized a dear old friend.
“He can’t have them, Michelle. I sold them at the corner,” Erkan shouted, pushing his way to Michelle. “He stole my guitar,” he whispered.
“I know, Erkan, but he was only trying to help you get some money to pay for your trip.” Michelle had been frightened by a lot of the residents of the nursing home when she first started the beginning of the semester. Many of them were incoherent and loud, and some could be very aggressive and scary. Erkan often pushed or kicked and ranted. Michelle had started to regret this internship, and she even avoided going near Erkan’s room whenever possible. “He lives in his own world,” Philip, the managing nurse, explained to Michelle after her first encounter with Erkan’s temper.
Still, Michelle had been curious, and she felt sorry that Erkan had a bad reputation among the staff. She too had felt like everyone mistrusted her—especially at the nursing home where she was so much younger than the rest of the staff—so she understood how he must feel. Besides, he was the only person in the whole place with skin nearly as dark as hers.
Over time, she noticed patterns in Erkan’s rants: He would sometimes mention his guitar and his father and the city of Diyarbakir, which she learned is in Turkey. So she decided that the next time she brought supplies to his room, instead of avoiding Erkan, she would play along with whatever he said. If he lived in his own world, then she would try to join him there. Bit by bit, she discovered that he had immigrated to the United States from Turkey when he was very young. His father had saved as much money as possible to pay for his journey, but he needed to sell Erkan’s guitar to help cover the cost. Erkan had moved in with his aunt’s family in Scranton, Pennsylvania, and finished school there. Eventually he got married, had children of his own, and worked for years signing Turkish singers to a small record label. But he’d never quite felt at home in the United States.
“I know he sold your guitar, but you told me yourself he just wants what’s best for you,” Michelle said, while Philip and the caregiver looked on in amazement as Erkan settled into an armchair. “Now why don’t you listen to Philip, take your shoes off, and have a shower?”
“For you, Michelle, I’ll do it.”
You can feel out of place in a country, in the place where you live, or even in your own head, Michelle thought. But if you’re lucky, someone will know how to find you and remind you that we all feel that way sometimes.
In “Out of Place,” how has Ekran’s relationship with Michelle affected him? Discuss interactions between the two characters and explain how Ekran reacts to these interactions. Use evidence from the text to support your response. Your response should be at least two complete paragraphs.
Answer:
Type your answer here

Answers

Answer:

Ben is being amazing

Explanation:

HELP AGAIN !!!!!!!!!!

Answers

Answer:

C

Explanation:

I'm not sure what the story is but I'm pretty sure

which sentence best rewrites the following line so that that it includes hyperbole?
Jackson lived for a long period of time in a small

Answers

Answer:

jackson lived forever

Explanation:

a hyperbole is an exaggeration

A figure of speech in which one directly addresses an absent or imaginary person, or some abstraction​

Answers

Answer:

apostrophe

Explanation:

Fat cat or neck fat? NO IS NOT A ANSWER EITHER A YES OR MAYBE SOMETHING ELSE

Answers

Answer:

Fat cat I guess. what's the question about

What is it called when you make overall changes to your document in revision?

Answers

Answer:

comprehensive

Explanation:

brainleist would be appreciative :)

Answer:

It is called comprehension.Hope this helps ;)


What is the size of the matrix resulting from

Answers

Answer:

Size of a matrix = number of rows × number of columns. It can be read as the size of a matrix and is equal to number of rows “by” number of columns. There are several popular types of matrices: 1

Number of rows x number of columns

Why does a bannana curve

Answers

Answer:

Bananas curve so they can get sunlight.

Explanation:

Hope this helps.

Other Questions
give one example of how the geosphere and the atmosphere interact in the carbon cycle PLEASE HELP IM GIVING OUT 30 POINTS!!!!Choose one of the animals listed on the page, and write a brief description of its characteristics. Be sure to discuss any ways (The animal is The Fennec Fox) Which of the following is NOT made with petroleum (oil)?N O cooking oilmedicineplasticO cleansers Read the quotation from "To My Dear Loving Husband.""I prize thy love more than whole mines of gold,Or all the riches that the East doth hold."These lines contain an example ofsimile.metaphor.hyperbole.synecdoche. Sharon went bowling with her friends. She paid $3 to renther shoes and then $3.75 for each game (x) of bowling. Shespent a total of $18. How many games did she bowl?WRITE YOUR EQUATION:SOLVE:SOLUTION: Dr. Bob Jackson owns a parcel of land that a local farmer has offered to rent from Dr. Bob for the next 10 years. The farmer has offered to pay $20,000 today or an annuity of $3,200 at the end of each of the next 10 years. Which pay-ment method should Dr. Jackson accept if his required rate of return is 10 percent Help me with this question pleasee PLEASE HELP!!! Chloe is working two summer jobs, landscaping and clearing tables. She must work no less than 12 hours altogether between both jobs in a given week. Write an inequality that would represent the possible values for the number of hours landscaping, l and the number of hours clearing tables, c, that Chloe can work in a given week. how many times 92 go in too 100 Read this passage from Dragonwings by Laurence Yep.The demon was a big, cheerful-looking demon with a bland, round face. He eyed father. "I dunno, John." Many demons called Tang men John because, they insisted, they never could get the hang of our real names. "You know anything about horselesses?""Some," Father said. Truth to tell, he had never handled a horseless carriage in his life, though he had a book on them and cut out articles whenever they appeared in the demon magazines and newspapers. That was the extent of Father's knowledge. But to know facts is nothing. He had an intuitive feeling for what made the horseless carriages tick. He looked around inside the engine for about ten minutes and then wiped his face absentmindedly, so that the grease stained his cheek. He did not even notice.Which quote from this passage is an example of indirect characterization?The demon was a big, cheerful-looking demon with a bland, round face.Many demons called Tang men John because, they insisted, they never could get the hang of our real names.He had an intuitive feeling for what made the horseless carriages tick.He looked around inside the engine for about ten minutes and then wiped his face absentmindedly, so that the grease stained his cheek. Which organelle would you expect to find in animal cells but not plant cells?O A. mitochondrionOB. ribosomeC. lysosomeO D. A. smooth endoplasmic reticulum What is |-24| + |13| =? Doug and Sue Click file a joint tax return and decide to itemize their deductions. The Clicks' income for the year consists of $89,000 in salary, $1,500 interest income, and $700 long-term capital loss. The Clicks' expenses for the year consist of $1,450 investment interest expense. Assuming that the Clicks' marginal tax rate is 35 percent, what is the amount of their investment interest expense deduction for the year Under the allowance method for uncollectible accounts, the journal entry to record the estimate of uncollectible accounts would include a credit to Write An Example Of Ethos In '' An Fable For Tomorrow'' Technology has changed the way that people move, live, and work. Now, technology is changing the way that people receive and react to news stories. News has become a community affair, instead of a job in the hands of the powerful news editors. Through the Internet, people can search for opinionated or unbiased news on just about every topic under the sun. Today, the powerful are not the news editors but the news bloggers. A Web log, or blog, is a space for a person to write down his or her ideas, thoughts, feelings, or even news. Many people in the U.S. have personal blogs, in which they share parts of their lives with total strangers around the world. Now, blogs are becoming increasingly important in the world of news. Reporters caught in the thick of battle can immediately post their thoughts and feelings on blogs. Amateur writers can become instant celebrities from their focus on a particular news-worthy subject. So what are these blogs doing to news? Simply put, they are personalizing news. Blogs are making it easier and faster for readers and Internet surfers to get a behind-the-scenes look at a story. Blogs are also making it easier for people to start conversations about news events, whether that is through comments made about a particular entry or a message board attached to the blog. The Internet in general has allowed people the opportunity to really bring news into their lives. Blogs are just one more way for people to connect to a news story. Unfortunately, blogs have their problems. If they are not attached to a well-known news Web site, like Reuters, CNN, or even your local paper, the blogs are often not fact-checked. Blogs are often more about a person's opinion about an event or a personal attachment to an event or story. They are less about the straight facts and more about the personal element of the story. People have to be very careful when reading blogs not attached to familiar news companies. The right blog can be an enjoyable and personal way to experience news and understand what is going on in the world. From a reporter on the campaign trail to a family living in Iraq, readers can find out many different views on a wide variety of stories. Blogs are just one more way for people to personalize and identify with news they might not otherwise see or hear about. Take a few minutes to find a blog that fits your interests. You might be surprised at what you learn!Select the correct answer.Which of the following statements supports the idea that the blogs are not always trustworthy?A."The Internet in general has allowed people the opportunity to really bring news into their lives."B."News has become a community affair, instead of a job in the hands of the powerful news editors."C."If they are not attached to a well-known news Web site . . . the blogs are often not fact-checked."D."Amateur writers can become instant celebrities from their focus on a particular news-worthy subject."Reset Read 3 integer numbers from the user; these numbers represent the lengths of 3 straight lines. From the 3 lengths, determine whether a triangle can be formed with the corresponding lines. If it is possible to form a triangle, determine whether the triangle is a right triangle or not. The rules to be used are: 1. To form a triangle where all lines ends meet (form vertices), the sum of the lengths of two sides must be greater than the length of the third side. This short video illustrates this concept: How to determine if the three sides make up a triangle. 2. Per the Pythagorean theorem: in a straight triangle, the square of the length of the longest side (the hypotenuse) is equal to the sum of the squares of the lengths of the other two sides. 3. The user can enter the lengths of each line in any order, i.e.: you may not assume that the first length is the longest or the smallest or the middle value. MULTIPLE CHOICE!!!WILL GIVE BRAINLIEST!!!20 POINTS!!!Why is the population of the Atacama Desert so small?-too many wild animals-annual flooding-barren area with little rainfall-industrial area only Saying words with meaning as if you were speaking them is called phrasing.Please select the best answer from the choices providedOT Given that almost all organisms obtain energy from food by the process of cellular respiration, which is the most likely explanation for what prevents Earth from running out of oxygen?