I couldn't find Peter, did I know where he had gone. [ ]
A. either
B. nor
C. so
D. and
答案:B
下列物质属于酯类的是①豆油②甘油③牛油④溶剂油⑤汽油⑥菜籽油⑦润滑油
A.②③④⑦
B.①③⑥
C.⑤⑥⑦
D.②⑤