题目

已知煤油的密度是0.8g•cm﹣3 ， 试根据金属钠的保存方法和金属钠与水反应的现象推断金属钠的密度（ ） A . 小于0.8 g•cm﹣3 B . 大于1.0 g•cm﹣3 C . 介于0.8～1.0 g•cm﹣3 D . 无法推测 答案：C听下面一段对话，回答1-4题。1.What did Nicholas do at eighteen months?A. He began to learn French. B. He read the newspaper. C. He took telephone messages.2.Why was Nicholas bored and unhappy at the two schools?A. He had too much homework.  B. He almost couldn't learn anything special.C. His teachers often corrected his spelling.3.Who offered to help Nicholas finally?A. His classmates.        B. His parents.   C.A college.4.What is Nicholas' life like now? A. Busy without any social life. B. Full but boring. C. Busy at college and free at home.