编写applet程序，显示一个小球在面板上弹跳，使用两个按钮暂停和重新开始小球的运动，使用一个滚动条控制小球的弹跳高度。-Write applet program that displays a small ball bouncing on the panel, using the two buttons to pause and re-start the ball movement, the use of a scroll bar control the ball bounce height.