一些小动物或人物的滑稽造型如不倒翁等是()
A.娱乐玩具
B.智力玩具
C.结构造型玩具
D.音乐玩具
参考答案:A
We advocate the disagreements between China and America _____ through dialogue. [ ]
A. must be settled
B. would be settled
C. be settled
D. are settled
重G的光滑小球静止在固定斜面和竖直挡板之间.若挡板逆时针缓慢转到水平位置,在该过程中,斜面和挡板对小球的弹力的大小F1、F2各如何变化( )
A.F1逐渐变小
B.F1先变小后变大
C.F2逐渐变小
D.F2先变小后变大