根据短文内容回答问题
It was very cold. It snowed heavily and blew very strongly. It was not a good night to go out. But David had to walk home from work “I can be warmer,” he thought, “I wear my coat backwards①.”He took off his coat and put it on backwards. “That’s much better.”He thought and walked on. About ten minutes later a car hit him. The driver stopped his car and got out of it. He ran to help David.
Soon a police car arrived. The policeman ran to look at David. “I’m afraid he’s dead.”The policeman told the driver.
The driver could not believe it.“He can’t be dead.”He cried,“I did not touch him. Look at my car. There is not a mark②on it.”
“He’s dead.”The policeman said again.
“I don’t understand it.”The driver said,“As soon as I hit him. I ran to help him. He was lying on the road, but he was breathing and there was no blood③.”
“Did you touch him?”The policeman asked.
“Yes,”The driver said,“but I only turn his head around the right way.”
Notes:
1. backwards adv.反方向地
2. mark n.印记
3. blood n.血
Read the passage and answer the following questions.（阅读短文，回答问题。）
1. Why was David walking in such bad weather?
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2. How did David make himself warmer?
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3. Did the driver run to help David?
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4. What did the policeman say again?
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5. Who killed David?
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