题干
13. He took ________ advantage of cultural resouces and succeeded in ________ 1990s.
A：an ; /
B：the ; the
C：an ; the
D：/ ; the
答案(点此获取答案解析）
D
A：an ; /
B：the ; the
C：an ; the
D：/ ; the
匀浆，分别置于甲、乙、丙三支试管中。向试管中滴加等量的丙酮酸后，可获得终产物CO2和水的试管是