题目

在一次考古科普知识展览会上，举办单位展出了2000多年前的一顶王冠，该王冠重5.6N，体积为30cm3。试问：它是否是用纯金制成的？为什么？请通过计算回答。（ρ金=19.3×103kg/m3 ， g取10N/kg） 答案：解：{#mathml#}m=Gg=5.6N10N/kg=0.56kg=560g{#/mathml#}∵，∴工艺品不是由纯金制成的听对话，从所给选项中选出最佳答案回答问题。 听两遍。听第一段对话，回答第1-2小题：1. Where is the mother going? [     ]A. She is going to school. B. She is going to the hospital. C. She is going to the supermarket. 2. What does the boy want? [     ] A. He wants a ball pen. B. He wants a pen. C. He wants a ball. 听第二段对话，回答第3-5小题： 3. What time was it when they thought of stopping the car? [     ]A. 10:30. B. 12:30.C. 2:30. 4. Why did they want to stop the car? [     ] A. To eat something. B. To have a walk.C. To look at the sheep. 5. Where did they decide to stop at last? [     ]A. In another field. B. In a small village.C. On a piece of grass. 听第三段对话，回答第6-7小题： 6. Where does the man want to go? [     ] A. The History Museum. B. The Science Museum. C. The park. 7. How far is it from here to the History Museum? [     ]A. About 500 metres. B. About 5.5 kilometres. C. About 6 kilometres. 听第四段对话，回答第8-10小题：8. Where is the new library? [     ] A. Near the museum. B. In London School. C. On Ocean Road. 9. What can they do in the video reading room? [     ]A. They can listen to tapes.B. They can borrow some books. C. They can search the Internet. 10. When can they see a free film? [     ]A. On Tuesdays.B. On Saturdays. C. On Sundays.