The teacher wondered whether those ______at the back of the classroom could hear him. A. seating B. sit C. seated D. sat
A、B两个质点在同一直线上运动，它们的位移—时间图像如图所示，图中两条直线平行，关于A、B两个质点的运动，下列说法中错误的是：（ ）A．它
若∠a＝79°25′，则∠a的补角是 （ ） A．100°35′ B．11°35′ C．100°75′ D．101°45
Shelly had prepared carefully for her driving test so that she could pass it at her first________. A．attempt B．intention C．desire
如图所示，绝缘杆两端固定带电小球A和B，轻杆处于匀强电场中，不考虑两球之间的相互作用．最初杆与电场线垂直，将杆右移的同时使其顺时针转过90
已知F1、F2是双曲线=1的焦点,PQ是过焦点F1的弦,那么|PF2|+|QF2|-|PQ|的值是_____________________.
China is the home of tea, 36 has more than 4,000 years of history. People in China drink tea daily. 37 the three major drinks ----tea, coffee and cocoa, tea is drunk by 38 people in the w
朱德曾赋诗道：“红军荟萃***，主力形成在此间。领导有方在百炼，人民专政靠兵权。”这首诗回忆了红军第一支坚强的队伍形成时的情景。诗中史实
