A:Mary had found
B:had Mary found
C:did Mary find
D:Mary found
如图是地球内部圈层示意图,读图回答下题.
法国大革命开始的标志是( )
甲、乙两人下棋,甲获胜的概率为13,两人下成和棋的概率为12,则乙不输的概率为____