题干
. He was afraid that the branch might bend over and break, and he would be sent _____ to the ground.
A：crashing
B：throwing
C：rushing
D：dropping
答案(点此获取答案解析）
A
2
匀减速上升的升降机中，最多可举起重力为800N的重物，则此人若站在地面上，最多可举起质量为（ ）的重物.(g=10