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import static javax.swing.JOptionPane.*;
import java.text.DecimalFormat;

class Question3 {

public static void main(String[] args) {

    String intrestRateStr = showInputDialog("What is the interest rate?");
        int intrestRate = Integer.parseInt(intrestRateStr);

    String depositStr = showInputDialog("How much will you deposit?");
        double depositAmount = Double.parseDouble(depositStr);

   DecimalFormat pounds = new DecimalFormat("£###,##0.00");

   double amountInterest = calcAmount(intrestRate, depositAmount);

   String bonusStr;
          double bonus = Double.parseDouble(bonusStr);

   if (amountInterest >= 5000.00)
       bonus = (+100.00);
   else if (amountInterest >= 1000.00)
       bonus = (+50.00);


   double finalAmountInterestBonus = bonus + amountInterest;

    showMessageDialog(null,
            "Your savings will become " + pounds.format(finalAmountInterestBonus));
}

private static double calcAmount(int intRate, double depAmount) {
    double result = depAmount*(1.0 + intRate/100.0);
    return result;
 }
}

String bonusStr;
double bonus = Double.parseDouble(bonusStr);

String bonusStr = "123.456";
double bonus = Double.parseDouble(bonusStr);

String bonusStr;
double bonus = Double.parseDouble(bonusStr);

String bonusStr;
          double bonus = Double.parseDouble(bonusStr);

String bonusStr = "0";