A.1-丁烯 2-丁烯
B.C4H10和C20H42
C.C4H8和C3H6
D.一溴乙烷和1,2-二溴乙烷
答案:B
谁将建文帝赶下台()
A、唐太宗
B、宋太祖
C、明太宗
D、清太祖
What do we know about Susan
A.She learned Spanish in America.
B.She doesn’t know Spanish.
C.She improved her Spanish in Mexico.
D.She knew Spanish before going to Mexico.