横线上填几?
8+____=11
8+____=16
6+____=15
11-8=____
16-8=____
15-6=____
---- Excuse me, could you please tell me the way to the nearest hospital?
---- I'm sorry, _I am new here. You can ask the policeman over there.
一个电子以3.2×106m/s的初速度沿电场线方向射入匀强电场,在电场中飞行了9.1×10﹣7s后开始返回,则匀强电场的场强大小为____,电子在匀强电场中从进入到返回原处所通过的路程为____.
如图,已知⊙O的直径AB为10,弦CD=8,CD⊥AB于点E,则sin∠OCE的值为( )