The Jmenus are not popping up when i run the program

Question

The JMenus are not popping up when i run the program but they will pop up when you expand the window gui program with faulty menus
everything else works fine but its just that the Jmenus are not popping up on run time im not sure what the problem is? the operations menu will sometimes pop up, this program is supposed to calculate future value so it takes in several integer inputs and outputs a future value but the only problem with it is the JMenus are not appearing on run time.

   import java.awt.*;
   import java.awt.event.*;
   import java.text.DecimalFormat;
   import javax.swing.*;
   import javax.swing.event.MenuEvent;
   import javax.swing.event.MenuListener;





    //[1]Create a class InvestCalc
    //[2]futureValue = investAmount * (1 + monthlyInterestRate)years * 12
    //[3]Use text fields for investment amount, annual interest rate, years, and future value


    //[4]The Operation menu contains two items: Calculate and Exit.                                                                                     
    //[5]Help menu displays how the future value is calculated in a JOptionPane



    public class InvestCalc implements ActionListener, MenuListener  {

    JFrame frame = new JFrame();
    JPanel panel = new JPanel();
    JMenuBar menuBar;

    private JLabel label1,label2,label3,label4;
    private JTextField textField1,textField2,textField3,textField4;
    private JButton button;
      //constructor
    public InvestCalc() {
        frame.setTitle("Assignment 11");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);

     frame.add(panel);

      frame.setSize(400,300);

        //adding the menu
        JMenuBar menuBar = new JMenuBar();
        frame.setJMenuBar(menuBar);
        JMenu operations = new JMenu("Operations");
        menuBar.add(operations);


        JMenuItem cal = new JMenuItem("Calculate");
        operations.add(cal);
        cal.addActionListener(null);
        cal.addActionListener(new event());


        JMenuItem exit = new JMenuItem("Exit");
        operations.add(exit);


        JMenu help = new JMenu("Help");
        menuBar.add(help);
        help.addMenuListener(this);






            //Exit button
    class exitAction implements ActionListener{

            public void actionPerformed (ActionEvent e) {
                System.exit(0);


            }
        }

    exit.addActionListener(new exitAction());





        //layout for panel 
        panel.setLayout(null);
        label1 = new JLabel("Investment Amount");
        panel.add(label1);
        label1.setBounds(20,35,165,25);
        textField1 = new JTextField(15);
        panel.add(textField1);
        textField1.setBounds(170, 35, 200, 25);

        label2 = new JLabel("Years");
        panel.add(label2);
        label2.setBounds(20,65, 165, 25);
        textField2 = new JTextField(15);
        panel.add(textField2);
        textField2.setBounds(170, 65, 200,25);


        label3 = new JLabel("Annual interest Rate");
        panel.add(label3);
        label3.setBounds(20,95,165,25);
        textField3 = new JTextField(15);
        panel.add(textField3);
        textField3.setBounds(170, 95, 200, 25);

        label4 = new JLabel("Future Value");
        panel.add(label4);
        label4.setBounds(20,125,165,25);
        textField4 = new JTextField(15);
        panel.add(textField4);
        textField4.setBounds(170,125,200,25);

        textField4.setBackground(Color.lightGray);
        textField4.setEditable(false);




        button = new JButton("Calculate");
        panel.add(button);
        button.setBounds(20, 175, 350, 30);
        event e = new event();
        button.addActionListener(e);


    }






//this section is for the calculate button on the button of the panel
public class event implements ActionListener{
    public void actionPerformed(ActionEvent e)
    {


        String x = textField1.getText();
        double investmentAmount = Double.parseDouble(x);

        String y = textField2.getText();
        int Years = Integer.parseInt(y);

        String z = textField3.getText();
        double annualInterestRate = Double.parseDouble(z);

        double FutureRate = investmentAmount * Math.pow((1 + (annualInterestRate/100)),(Years));

        DecimalFormat df = new DecimalFormat();
        df.setMaximumFractionDigits(2);
        textField4.setText("$"+String.valueOf(df.format(FutureRate)));
    }}




//main method
public static void main (String[] args) {

    //constructor
    new InvestCalc();

}



@Override
public void menuCanceled(MenuEvent e) {
    // TODO Auto-generated method stub

}



@Override
public void menuDeselected(MenuEvent e) {
    // TODO Auto-generated method stub

}


//clicking of the help menu
@Override
public void menuSelected(MenuEvent e) {
    // TODO Auto-generated method stub
    JOptionPane.showMessageDialog(null,"This is the Formula used to determine future value\n"
            +"futureValue = investAmount * (1 + monthlyInterestRate)years * 12");

}



@Override
public void actionPerformed(ActionEvent arg0) {
    // TODO Auto-generated method stub

}


}