With these words, Tom went on ________ his homework.
A:do
B:to doing
C:doing
D:does
①MB∥平面A1DE;
②|BM|是定值;
③A1C⊥DE.
某同学用显微镜观察时,若目镜为5×,物镜为10×,则物像的放大倍数是( )
黄小明在他的旅游日记当中写道:“今天,我看到了金字塔和狮身人面像。”那么他到达的国家应该是( )