汽油机排气冲程结束，这时温度约为（）。

A、100～200K

B、900～1200K

C、600～900K

D、500～600K

本题的功能是对图形进行操作，包括旋转、移位、放大和剪切。窗口中有4个单选按钮和一个图形面板，图形面板中有一个矩形和该矩形移位操作后的图形，任选其中一个单选按钮，则图形面板中将显示该操作后的图形。单选按钮，则图形面板中将显示该操作后的图形。
import java. awt. * ;
import java. awt. event. * ;
import java. awt. geom. * ;
import java. util. * ;
import javax. swing. * ;
public class java3

public static void main(String[] args)

JFrame frame=new TransformTestFrame();
frame. setDefaultCloseOperation(JFrame. EXIT_ON_CLOSE);
frame. show();


class TransformTest extends JFrame

public TransformTestFrame()

setTitle("java3");
setSize(WIDTH, HEIGHT);
Container contentPane=getContentPane();
canvas=new TransformPanel();
contentPane. add(canvas, BorderLayout. CENTER);
JPanel buttonPanel=new JPanel();
ButtonGroup group=new ButtonGroup();
JRadioButton rotateButton
=new JRadioButton("旋转", true);
buttonPanel. add(rotateButton);
group. add(rotateButton);
rotateButton. addActionListener(new
ActionListener()

public void actionPerformed(ActionEvent event)

canvas. setRotate();

);
JRadioButton translateButton
=new JRadioButton("移位", false);
buttonPanel. add (translateButton);
group. add(translateButton);
translateButton. addActionListener (new
ActionListener()

public void actionPerformed(ActionEvent event)

canvas. setTranslate();

);
JRadioButton scaleButton
=new JRadioButton("放大", false);
buttonPanel. add(scaleButton);
group. add(scaleButton);
scaleButton. addActionListener(new
ActionListener()

public void actionPerformed(ActionEvent event)

canvas. setScale();

);
JRadioButton shearButton
=new JRadioButton("剪切", false);
buttonPanel. add(shearButton);
group. add(shearButton);
shearButton. addActionListener(new
ActionListener()

public void actionPerformed(AetionEvent event)

canvas. setShear();

);
contentPane. add(buttonPanel. BorderLayout. NORTH);

private TransformPanel canvas;
private static final int WIDTH=300;
private static final int HEIGHT=300;

class TransformPanel extend JPanel

public TransformPanel()

square = new Rectangle2D. Double(-50,-50,100,100);
t=new AffineTransform();
setRotate();

public void paintComponent()

super. paintComponent(g);
Graphics2D g2=(Graphics2D)g;
g2. translate(getWidth()/2, getHeight()/2);
g2. setPaint(Color, gray);
g2. draw(square);
g2. transform(t);
g2. setPaint(Color. black);
g2. draw(square);

public void setRotate()

t. setToRotation(Math. toRadians(30));
repaint();

public void setTranslate()

t. setToTranslation(20,15);
repaint();

public void setScale()

t. setToScale(2.0,1.5);
repaint();

public void setShear()

t. setToShear(-0.2,0);
repaint();
private Rectangle2D square;
private AffineTransform t;