My little son asked ________.
A:that his father would come back in an hour
B:what's the matter with his sister
C:who could help him finish his homework
D:how long they had been to Wuxi
丙同学采用频闪摄影的方法拍摄到如图所示的小球做平抛运动的照片,图中每个小方格的边长为L=1.25cm,则由图可求得该小球做平抛运动的初速度大小为____m/s.(g取9.8m/s2)
陈浩尝试植物扦插实验,如图,最容易成活的是( )
阅读下面这首宋诗,然后回答小题.
雨后池上
刘攽
一雨池塘水面平,淡磨明镜①照檐楹②。
东风忽起垂杨舞,更作荷心万点声。
【注释】①淡磨明镜:形容水面平静,池水清澈。
②檐楹:屋檐及檐下的堂柱。