题目

A sign is another kind of language. Here are some of them that you see on the roads.Number one is a sign with the number thirty on it. When drivers see this sign , they must not go at more than thirty kilometers can hour. We see this sign when we are getting near a town. Number two is a sign that we're near a crossing. We must drive carefully. Number three is a sign that there is a bend in the road. Again, we must drive slowly and carefully. It is not safe to go round a bend very fast. Number four is a sign that there is another road coming in from the right. There is a junction at this place.现有三组混合物:①汽油和水;②汽油和柴油;③氯化钠和单质碘的水溶液,正确的分离方法依次是:A.分液、萃取、蒸馏B.萃取、蒸馏、分液C.分液、蒸馏、萃取D.蒸馏、萃取、分液
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