题目

听下面一段独白，回答以下小题。【1】What is the speaker mainly talking about?A.Tibetan history.B.A popular book.C.His traveling experiences.【2】When did the speaker start to visit Tibet?A.About 10 years ago. B.About 39 years ago. C.About 60 years ago.【3】Who did the speaker go to Tibet with?A.A scientist. B.His wife. C.Tintin.【4】Which of the following impressed the speaker most in Tibet?A.Mount Qomolangma. B.The Tibetan people. C.The Potala Palace.将某金属片进入烧碱溶液一小段时间后，取出洗净再放入硝酸汞溶液中，表面逐渐附着一层灰白色的固体，取出后用滤纸轻轻地将其表面吸干，然后将其置于干燥的滤纸上，片刻后即观察到，其表面生出白色毛状物，则原金属及毛状物分别是 、 ．