—What did you do yesterday evening, Gina?
—I __________Titanic 3D in the City Cinema.
A:watch
B:watched
C:am watching
D:will watch
为宣传维新变法,康有为、梁启超创办了( )
(3x-1x)n的展开式中各项系数之和为64,则展开式的常数项为( )