单项选择题
A.abcd B.bacd C.bcad D.acbd
A.正己烷 B.正戊烷 C.异戊烷 D.新戊烷
A.CH2BrCH(CH3)CH2CH3 B.(CH3)2CBrCH2CH3 C.(CH3)2CHCHBrCH3 D.(CH3)2CHCH2CH2Br