下列反应属于化合反应的是（ ）
A．乙炔+氧气点燃二氧化碳+水
B．氢气+氧气点燃水
C．氧化汞△汞+氧气
D．水通电氢气+氧气
答案：B
情景对话，选择正确句子补全对话。
A. Do you like these white socks?
B.May I help you?
C.How much is this pair?
D. Do you have other colours?
E.I'll take two pairs.
A: Good afternoon!
B: Good afternoon!
A: 1.__________
B: Yes.I want to buy some socks.
A: 2.__________
B: Sorry.I don't like white.3.__________
A: Yes.Here are red and black socks.
B: I want these black socks.4.__________
A: Five dollars.
B: OK. 5.__________
A: Well.Here you are.
（）不属于试验工作的内容。
A.数据采集
B.干扰波调查
C.地震地质条件的了解
D.激发因素的选择
