题目

You must be tired. Why not_________ a rest?         A. to stop to have      B. to stop having     C. stop to have    D. stop having   答案：C如图是实验室加热高锰酸钾制取并收集氧气的装置图．（1）指出装置中有标号的仪器名称③______⑤______（2）改正图中三处明显的错误：①______  ②______③______．