Help with error

[Anime101]

I'm trying to do a tutorial out of book, but I keep geting errors, the errors I got are listed at the bottom of the page. Here's the code:
Thanks for any help given.

import java.awt.*;
import java.applet.*;
import java.awt.event.*;
import java.text.DecimalFormat;

public class CommissionApplet extends Applet implements ItemListener
{
//declare variables and construct a color
double dollars, answer;
int empCode;
Image dollarSign;
Color darkRed = new Color(160, 50, 0);

//Create components for applet
Label promptLabel = new Label ("Enter sales amount(do not use commas or dollar signs):");
TextField salesField = new TextField (20);

Label codeLabel = new Label ("Select the appropriate commission code:");

CheckboxGroup codeGroup = new CheckboxGroup();
CheckBox telephoneBox = new Checkbox("Telephone Sales",false,codeGroup);
CheckBox inStoreBox = new Checkbox ("In-Store Sales",false,codeGroup);
CheckBox outsideBox = new Checkbox("Outside Sales",false,codeGroup);
CheckBox hiddenBox = new Checkbox ("",true,codeGroup);

Label outputLabel = new Label ("Click an option button to calculate the sales commission.");

public void init()
{
setBackground (darkRed);
setForeground (Color.white);
add(promptLabel);
add(salesField);
salesField.requestFocus();
salesField.setForeground(Color.black);
add(codeLabel);
add(telephoneBox);
telephoneBox.addItemListener(this);
add(inStoreBox);
inStoreBox.addItemListener(this);
add(outsideBox);
outsideBox.addItemListener(this);
add(outputLabel);
}

//This method is triggered by the user clicking an option button
public void itemStateChanged(ItemEvent choice)
{
try
{
dollars = getSales();
empCode = getCode();
answer = getComm(dollars,empCode);
output(answer,dollars);
}

catch(NumberFormatException e)
{
outputLabel.setText("You must enter a dollar amount greater than zero.");
hiddenBox.setState(true);
salesField.setText("");
salesField.requestFocus();
}
}

public double getSales()
{
double sales = Double.parseDouble(salesField.getText());

if (sales <= 0) throw new NumberFormatException();

return sales;
}

public int getCode()
{
int code = 0;
if (telephoneBox.getState()) code = 1;
else
if (inStoreBox.getState()) code = 2;
else
if (outsideBox.getState()) code= 3;
return code;
}

public double getComm(double sales, int code)
{
double commission = 0.0;
switch (code)
{
case 1:
commission = .10 * sales;
break;

case 2:
commission = .14 * sales;
break;

case 3:
commission = .18 * sales;
break;
}
return commission;
}

public void output (double commission, double sales)
{
DecimalFormat twoDigits = new DecimalFormat("$#,000.00");
outputLabel.setText("Your commission on sales of " + twoDigits.format(sales) +
" is " + twoDigits.format(commission));
}
public void paint (Graphics g)
{
dollarSign = getImage(getDocumentBase(), "dollarSign.gif");
g.drawImage(dollarSign,12,28,this);
}
}


And here's the error's I get when I compile


G:\CommissionApplet.java:30: cannot find symbol
symbol : class CheckBox
location: class CommissionApplet
CheckBox telephoneBox = new Checkbox("Telephone Sales",false,codeGroup);
^
G:\CommissionApplet.java:31: cannot find symbol
symbol : class CheckBox
location: class CommissionApplet
CheckBox inStoreBox = new Checkbox ("In-Store Sales",false,codeGroup);
^
G:\CommissionApplet.java:32: cannot find symbol
symbol : class CheckBox
location: class CommissionApplet
CheckBox outsideBox = new Checkbox("Outside Sales",false,codeGroup);
^
G:\CommissionApplet.java:33: cannot find symbol
symbol : class CheckBox
location: class CommissionApplet
CheckBox hiddenBox = new Checkbox ("",true,codeGroup);
^
4 errors

Tool completed with exit code 1

[masijade]

Checkbox not CheckBox