题目

You had better take the map with you ________ you won't get lost. A . as long as B . as soon as C . so that D . because 答案：C下列有关热现象及其解释中正确的是（ ）A．冬天早晨常出现大雾，是由于升华形成的B．夏天打开冰棍包装纸时常冒“白气”，是由于升华形成的C．秋天出现的白霜，是由于凝华形成的D．冬天窗户玻璃上有时出现小水珠，是由于凝华形成的