单项选择题
A.1~5s B.5~10s C.10~15s D.25~30s
A.0.5~1L/min B.1~3L/min C.5~6L/min D.6~7L/min
A.10mL B.20mL C.30mL D.40mL
A.2片苏打片 B.2mL三氯甲烷 C.2g明矾 D.2滴酸碱指示剂
微信扫一扫,加关注免费搜题