根据短文理解, 从A、B、C三个选项中选择最佳答案填空。
What do you usually do at the weekend? Some people like to stay at home, but some like to go 1 or to play football. My friend Wang Hai works 2 a school. At the weekend, he 3 the same thing. 4 Saturday he washes his car, and on Sunday he goes to the village 5 his family. His aunt and uncle have a 6 there. It isn't a big one, but there's always 7 work to do. In autumn, the children 8 them pick apples. Wang Hai and 9 wife help in the field. In the evening, they are all hungry and Wang Hai's aunt give them a big 10.
重力加速度为g，则物
块上升的最大高度和返回到原抛出点的速率分别为( )