The dam will generate electricity _____ about 40 million tons of coal without causing so much air pollution. A. equal B. be equal C. equal to D. be equal to 答案:C 解析: 略如图所示,AB为斜面,BC为水平面。从A点以水平初速度v向右抛出一小球,其落点与A的水平距离为S,若从A点以水平初速度2v向右抛出同一小球,其落点与A的水平距离为L,不计空气阻力,则L与S的比值不可能为( )A.1:2 B.3:1 C.1:4 D.5:2