They are going to the library ________ the afternoon ________ January 22nd.
A:at; at
B:in; of
C:on; of
D:to; at
如图,点E、F、G、H分别为菱形A1B1C1D1各边的中点,连接A1F、B1G、C1H、D1E得四边形A2B2C2D2,以此类推得四边形A3B3C3D3…,若菱形A1B1C1D1的面积为S,则四边形AnBnCnDn的面积为____.
已知3x+4x2-x-2=Ax-2﹣Bx+1,其中A、B为常数,则4A﹣B的值为( )