题目

下列能量的转化过程中，属于化学变化的是（   ） A．水力发电                            B．煤燃烧发电           C．太阳能热水器提供热水       D．电取暖器取暖 答案：B选择适当的句子完成对话。 B: I want to buy a sweater for myself. A: ___1___. B: I want to look at those woolen ones. A: ___2___. B: I like blue better. A: ___3___. B: That blue is too light. A: ___4___. B: Yes. That's just right. It's nice and soft, too. ___5___. A: Of course. 1．________2．________3．________4．________5．________