—Lingling, do you know ___________ woman in white? —Yes, she is __________ nurse in Children's Hospital.
A:a, a
B:the, the
C:a, the
D:the, a
用代入法解方程组有以下过程,其中错误的一步是( )
(1)由①得x=8-3y2③;
(2)把③代入②得3×8-3y2﹣5y=5;
(3)去分母得24﹣9y﹣10y=5;
(4)解之得y=1,再由③得x=2.5.
某跨国公司专门为为黑色人种配制的化妆品,价格低廉。下列大洲或地区中可能拥有较大销售市场的是( )