What _________ to your nose?[ ]
A. happened
B. happned
C. happen
D. happening
答案:A
(-a2)2n+1的计算结果是( )
A.a4n+2
B.-a4n+1
C.-a4n+2
D.a4n+1
价值形成过程是
A.生产剩余价值的过程 B.再创造生产资料价值的过程C.活劳动创造新价值的过程 D.物化劳动的旧价值的转移过程