题干

关于弹力的理解下列说法正确的是

A:弹力产生的原因是由于受力物体发生了形变

B:两个物体只要相互接触就会有弹力

C:任何物体间的弹力都遵守胡克定律

D:绳子的张力是弹力,其方向沿着绳子指向绳子收缩方向

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D

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    “Daily Star, sir” called Jason, carrying some newspapers under his arm. The little boy had been running up and down the street, but there were still twenty1 left. His voice was almost gone and his heart was 2. The shops would soon close, and all the people would go home. He would have to go home too, carrying the papers3money. He had hoped to sell more papers tonight to make more money to buy a 4for his mother and some seeds for his bird. That was why he had bought the papers with all his money. He 5as he thought of his failure to sell all his papers.

    “You don't know the 6 of selling papers. You must shout, “Hot news! Bomb bursting!” another newsboy Chad told Jason. “7 it's not in the paper at all,” replied Jason. “Just run away quickly 8 they have time to see, and you'll 9 out and get your money,”Chad said.

    It was a new 10 to Jason. He thought of his bird with no11 and the cake he wanted to buy for his mother, but was12 that he would not tell a lie. Though he was13a poor newsboy, he had been 14 some good things.

    The next afternoon Jason went to the office for his papers15 .Several boys were crowding around Chad, who declared with a 16 smile that he sold six dozen the day before. He added that Jason 17 money because he would not tell a lie. The boy 18 at Jason. “You wouldn't tell a lie yesterday, my boy?” A gentleman at the office came up and patted Jason's shoulder 19 .”You're just the boy I am looking for.” A week later Jason started his new20. He lost sale of twenty papers because he would not tell a lie, but got a well-paid job because he told the truth.