Let's together next Sunday.
A:do homework
B:play the piano
C:play sports
已知等比数列{an}的公比q=-13,则a1+a3+a5+a7a2+a4+a6+a8等于( )
随着沪宁城际高铁、武广高铁、京沪高铁等高铁正式通车运营,标志着我国步入高速铁路时代。饮水思源,火车机车的发明者是( )
-- _________.