题型:问答题 简答题 They have saved 90 people, _____ last year. [ ]A. twice of many B. twice as many asC. twice more D. twice as much as 查看答案
题型:问答题 简答题 武广高铁已通车运行,速度最高可达390Km/h,转弯时的半径达到了8 Km。若机车在运行过程中所受的阻力大小始终不变,在某一段直线轨道上匀加速运动的过程中,下列说法正确的是( )A.机车输出功率逐渐增大B.机车输出功率不变C.机车一直匀加速运动,直到最大速度D.在任意两相等的时间内,机车动能变化相等 查看答案