题目

The wonders of Virtual Reality (VR) (虚拟现实) can now take you back into a world that no person has ever seen. In this amazing new VR game, you will go back __1__ 100 million years, and live among the dinosaurs (恐龙). You will __2__ dinosaurs eat, sleep and fight. You will admire the great __3__ of the strange flowers and huge trees. You will __4__ a huge, friendly dinosaur with your hands. You will glide- through the __5__ on the back of a flying dinosaur and look down on the land and seas far __6__ you. You will watch a terrifying struggle, as two of the world’s most __7__ and dang以v的速度竖直向上抛出一物体，如果忽略空气阻力的影响，求：（1）物体上升的最大高度h；（2）物体的重力势能为动能的一半时，物体离抛出点的高度h1；（3）物体的重力势能和动能相等时，物体离抛出点的高度h2；（4）物体的动能是重力势能的一半时，物体离抛出点的高度h3；（5）物体的速率减为时，物体离抛出点的高度h4．（要求h1、h2、h3、h4都用与最大高度h的关系来表示）