题目

下列实验操作正确的是( ) A.用酒精萃取溴水中的溴单质的操作可选用分液漏斗，而后静置分液 B.分液时,分液漏斗下层液体从下口放出,上层液体从上口倒出 C.先在天平两个托盘上各放一张相同质量的纸,再把氢氧化钠固体放在纸上称 D.萃取分液前不需要对分液漏斗检漏 答案：B— ________________— My birthday is October twenty-second. [     ]A. How old are you? B. When is your birthday?