观察右表,导致该时期数字呈现大幅增长的主要原因是
A.英法联军攻占北京
B.甲午战争签订《马关条约》
C.列强在华划分势力范围
D.维新变法学习西方,引进外国资本
答案:B
The disinfection of various compartments in a vessel by filling with a gaseous agent to destroy rats and all insects pests which act as germ carriers means().
A.displacement
B.fumigation
C.discharging
D.compensation
比色法测定水溶性酸的影响因素有哪些?