题目

如图所示，小球从竖直砖墙某位置静止释放，用频闪照相机在同一底片上多次曝光，得到了图中1、2、3、4、5…所示小球运动过程中每次曝光的位置。频闪照相机的频闪周期为T，每块砖的厚度为d。根据图中的信息，下列判断正确的是  （    ） A．位置“1”是小球释放的初始位置 B．小球下落的加速度为        C．小球在位置“3”的速度为 D．小球在位置“5”的速度为A boy selling magazines walked up to a house that very few people visited. The house was old and the owner came out. The boy’s parents told him to stay away from the house. A lot of other neighbourhood children were told the same from their parents.As he was to walk away, the door slowly opened. "What do you want?" the old man asked. The little boy was very afraid at first. “Uh, sir, I'm selling these magazines and I was wondering if you'd like to buy .” The old man just stared at the boy. The boy could see that he had figurines（小雕像）on a table near the door．"Do you collect dogs?" the boy asked. "Yes, I do．They're my families here." The boy then the man, as it seemed that he was a very lonely person. "Well, I do have a magazine here for collectors. It's very good for , especially with a cover about dogs.” The old man was ready to close the door and said, “No, boy, I don’t need any .”The boy was sad that he was not going to finish his job for the day. He also felt sad the old man being so alone in the big house. The boy went home and then had a/an . He had a little dog figurine that he got from his aunt. The figurine did not mean to him because he had a lovely dog and a large family. The boy back for the old man's house with the figurine. He knocked at the door again and the old man came to the door. “Boy, I thought I had told you I didn’t need magazines.”“No, sir, I wanted to bring you a gift.” The boy handed him the figurine and the old man's face . "I have one at home. This one is for you.” The old man was simply ; no one had ever shown him so much . From that day on the old man started coming out of the house and talking with people. He and the boy became friends.1.A. always B. usually C. hardly D. frequently2.A. quick B. ready C. straight D. last3.A. one B. ones C. it D. them4.A. magazine B. house C. boy D. dog5.A. was sorry for B. was grateful to C. was satisfied with D. was proud of6.A. me B. you C. him D. them7.A. magazines B. friends C. dogs D. figurines8.A. in B. towards C. for D. with9.A. expression B. journey C. word D. idea10.A. more B. much C. many D. less11.A. walked B. ran C. hurried D. headed12.A. and B. so C. but D. as13.A. lit up B. gave up C. pack up D. came up14.A. shocked B. troubled C. frightened D. worried15.A. thanks B. money C. kindness D. help