Wu Yifan is _____________ a report.[ ]
A. writes
B. writing
C. write
答案：B
用蒸馏法测定食品中亚硫酸盐，应采用下列哪种方法（）。
A.重铬酸钾法
B.碘量法
C.酸碱滴定法
D.沉淀滴定法
E.比色法
A tank which carries liquid is dangerous to the stability of a vessel when it is（）.
A.low in the vessel
B.completely empty
C.completely full
D.slack
