题目

如图所示，一根轻弹簧下端固定，竖立在水平面上.其正上方A位置有一只小球.小球从静止开始下落，在B位置接触弹簧的上端，在C位置小球所受弹力大小等于重力，在D位置小球速度减小到零.小球下降阶段下列说法中不正确的是(     ) A.小球从A→D的过程，小球机械能守恒 B.在C位置小球动能最大 C.从A→C位置小球重力势能的减少大于小球动能的增加 D.从A→D位置小球重力势能的减少等于弹簧弹性势能的增加  完形填空。     A is a new student. Mr. Wang is asking him some questions. ?W: are new here, am I right?A: Yes, you are right, Mr. Wang. W:  1  ?A: Yes, what are they?W:   2  ?A: On July 14, 1983. W: Where were you born?A: I was born in Sydney in Australia. W:   3  ?A: For about eight years. W: And  4  ?A: They were born in Sydney, too. W: Are they living in China?A:  5  . He is coming soon. (    )1. A. May I ask you some questions           B. Shall I ask you any questions           C. Can you ask me any questions           D. Do you have any questions(    )2. A. Where were you born           B. When were you born            C. Who was born on July 14, 1983           D. Were you born on July 14, 1983(     )3. A. How often did you live there           B. How did you live there           C. Why did you live there           D. How long did you live there(     )4. A. Were your parents born in Sydney, too           B. Who were born in Sydney           C. Where were your parents born           D. When were your parents born(     )5. A. Mum is, but Dad works in Sydney           B. Mum does, but Dad works in Sydney           C. Dad is, but Mum works in Sydney           D. Dad does, but Mum works in Sydney