A.物体间不相互接触,也能产生弹力
B.只要物体接触就一定会产生弹力
C.发生弹性形变的物体,形变越大,弹力越大
D.只有弹簧才产生弹力
答案:C
The passengers were at ________ loss when ________ word came that their voyage was called off because of the hurricane.
A.the; a
B.a; the
C.a;/
D./; a
公元97 年,受班超派遣出使大秦的是[ ]
A.甘英
B.班固
C.窦宪
D.窦固