[说明]
以下程序实现了利用鼠标任意移动圆形的位置，仔细阅读代码和相关注释，将程序补充完整。
[代码6-1]
import java.awt.*;
import java.awt.event.*;
public class CIUSAMPLE extends Frame implements MouseMotionListener, MouseListener

static CIUSAMPLE frm=new CIUSAMPLE ( );
int x=70,y=60,posX=70,posY=60,dx,dy;
public static void main (String args[])

frm.setTitle ("Dragging a circle");
frm.setSize (200,150);
(1)
ffm.addMouseMotionListener (frm);
frm.setVisible (true);

public void mousePressed (MouseEvent e)

(2)
dy=e.getY ( ) -posY;

public void mouseDragged (MouseEvent e)

(3)
y=e.getY ( ) -dy;
if(dx＞0&&dx＜50&&dy＞0&&dy＜50) //如果指针落在正方形区域内

Graphicsg=getGraphics ( );
(4)


public void paint (Graphics g)

g.setColor (Color.pink); //设置绘图颜色为粉红
g.fillOval(x,y,50,50); //以基准点为图形在左上角绘出圆形
(5)
posY=y；

public void mouseMoved (MouseEvent e)
public void mouseReleased (MouseEvent e)
public void mouseEntered (MouseEvent e)
public void mouseExited (MouseEvent e)
public void mouseClicked (MouseEvent e)

视网膜电图中b波下降，a波正常，常见的眼病是（）

A.视网膜脱离

B.脉络膜炎

C.视网膜脉络膜炎

D.广泛视网膜光凝后

E.视网膜静脉阻塞