铜可溶于()
A、硝酸
B、盐酸
C、稀硫酸
D、浓硫酸
参考答案:A
客户对客户的电子商务类型简称为
A.B2B
B.G2G
C.E2E
D.C2C
29.It will lead to very serious result if this matter was ______ unsolved.
A.stayed
B.remained
C.left
D.Keeping