N-亚硝基化合物的前体物为亚硝酸盐、胺类和()
A.磷酸盐
B.硫酸盐
C.硝酸盐
D.碳酸盐
E.盐酸盐
参考答案:C
—What are you going to do this Sunday?
—I'd like some washing. [ ]
A.doing
B.to do
C.do
D.will do
加工贸易分册有独立编号,可以与原手册分开使用。