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问题 填空题

1.Look!All the people are looking in the d       of the corner.What’s happening there?

2.How f       it is outside.You see,everything is covered with ice.

3.There was no a       for the police but to set the young man free,for they didn’t have enough

evidence although they were sure it was he who committed the murder.

4.Can you see the bottle f       on the river?There seems to be a piece of paper in it.

5.Terry can’t p       in the match because he has hurt his foot.

6.Mr.Green worked so hard that      (最后) he made himself ill.

7.After the air crash,few people on board       (幸存) at last,which brought sadness to many families.

8.Mother      (测量) me to see what size of dress I should have.

9.Study the facts again and maybe you’ll draw a different       (结论).

10.Anyone who wants to get       (更进一步的) information can get in touch with us at any time.

答案

1direction   2freezing   3alternative   4floating   5participate   e6ventually  7 survived   8measured  

9conclusion    10further

问答题

在一次抗洪抢险活动中，解放军某部运用直升机抢救一重要落水物体，在静止在空中的直升机上用电动机通过悬绳将物体从离飞机90m处的洪水中吊到机舱里，已知物体的质量为80kg，吊绳的拉力不能超过1200N，电动机的额定输出功率为12kW，为尽快把物体安全救起，操作人员采取的办法是：先让吊绳以最大的拉力工作一段时间，达额定功率后电动机以额定功率工作，当物体到达机舱时它达到最大速度。（g=10m/s2）

　　求：（1）落水物体刚到达机舱时的速度；

　　　　（2）这一过程所用的时间。
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多项选择题

本题的功能是在文本域面板中添加一个带有行数的面板。窗口中有一个文本域，在文本域的左侧有一个带有数字的面板，该面板上的数字指示着文本域中的行数。
import javax.swing.*;
import javax.swing.event.*;
import java.awt.*;
public class java3 extends JFrame

public static JTextPane textPane;
public static JScrollPane scrollPane;
JPanel panel;
public java3()

super("java3()");
panel=new JPanel();
panel.setLayout(new BorderLayout());
panel.setBorder(BorderFactory.createEmptyBorder(20,20,20,20));
textPane=new JTextPane();
textPane.setFont(new Font("monospaced",Font.PLAIN,12));
scrollPane=new JScrollPane(textPane);
panel.add(scrollPane);
scrollPane.setPreferredsize(new Dimension(300,250));
setContentPane(panel);
setCloseOperation(JFrame.EXIT_ON_CLOSE);
LineNumber lineNumber=new LineNumber();
scrollPane.setRowHeaderView(lineNumber);

public static void main(String[]args)

java3 ttp=new java3();
ttp.pack();
ttp.setVisible(true);


class LineNumber extends JTextPane

private final static Color DEFAULT_BACKGROUND=Color.gray;
private final static Color DEFAULT_FOREGROUND=Color.black;
private final static Font DEFAULT_FONT=new Font("monospaced",Font.PLAIN,12);
private final static int HEIGHT=Integer.MAX_VALUE-1000000;
private final static int MARGIN=5;
private FontMetrics fontMetrics;
private int lineHeight;
private int currentRowWidth;
private JComponent component;
private int componentFontHeight;
private int componentFontAscent;
public LineNumber(JComponent component)

if(component==null)

setBackground(DEFAULT_BACKGROUND);
setForeground(DEFAULT_FOREGROUND);
setFont(DEFAULT_FONT);
this.component=this;

else

setBackground(DEFAULT_BACKGROUND);
setForeground(component.getForeground());
setFont(component.getFont());
this.component=component;

componentFontHeight=component.getFontMetrics(component.getFont()).getHeight();
componentFontAscent=component.getFontMetrics(component.getFont()).getAscent();
setPreferredWidth(9999);

public void setPreferredWidth(int row)

int width=fontMetrics.stringWidth(String.valueOf(row));
if(currentRowWidth＜width)

currentRowWidth=width;
setPreferredSize(new Dimension(2*MARGIN+width,HEIGHT));


public void setFont(Font font)

super.setFont(font);
fontMetrics=getFontMetrics(getFont());

public int getLineHeight()

if(lineHeight==0)
return componentFontHeight;
else
return lineHeight;

public void setLineHeight(int lineHeight)

if(lineHeight＞0)
this.lineHeight=lineHeight;

public int getStartOffset()

return component.getInsets().top+componentFontAscent;

public void paintComponent(Graphics g)

int lineHeight=getLinerteight();
int startOffset=getStartOffset();
Rectangle drawHere=g.getClipBounds();
g.setColor(getBackground());
g.fillRect(drawHere.x,drawHere.y,drawHere.width.drawHere.height);
g.setColor(getForeground());
int startLineNumber=(drawHere.y/lineHeight)+1;
int endLineNumber=startLineNumber+(drawHere.height/lineHeight);
int start=(drawHere.y/lineHeight)*lineHeight+startOffset;
for(int i=startLineNumber;i＜=endLineNumber;i++)

String lineNumber=String.valueOf(i);
int width=fontMetrics.stringWidth(lineNumber);
g.drawstring(lineNumber,MARGIN+currentRowWidth-width,start);
start+=lineHeight;

setPreferredWidth(endLineNumber);
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