—When _____ you _____ this book?

—I ____ it for two weeks.

A. have; bought; have had

B. did; buy; have had

C. have; bought; bought

D. did; buy; have bought

从地面上方同一点向东与向西分别平抛出两个等质量的小物体，抛出速度大小分别为v和2v，不计空气阻力，则两个小物体, 以下说法不正确的是:

A．从抛出到落地速度的增量相同

B．从抛出到落地重力做的功相同

C．从抛出到落地重力的平均功率相同

D．从抛出到落地所用时间不同