保安等级3时应对正在装卸的货物进行严格的检查。
参考答案：错
------Poor Steve! I could hardly recognize him just now!
------_______________, He has changed so much.
A．Never mind
B．No problem
C．Not at all
D．Me neither
标准方法规定在配制草酸标准溶液时，应使用（）
A.无水草酸
B.二水合草酸
C.四水合草酸
------_______________, He has changed so much.