VB 10 Problem with program

Write a complete Visual Basic program to do the following:
Joe’s Pizza Palace needs an application to calculate the number of slices
a pizza of any size can be divided into.
The application should do the following:
 Allow the user to enter the diameter of the pizza, in inches.
 Calculate the number of slices that can be cut from a pizza that size.
 Display a message that indicates the number of slices.
To calculate the number of slices that can be cut from the pizza, you must know these facts:
 Each slice should have an area of 14.125 inches.
 To calculate the number of slices, divide the area of the pizza by 14.125.
 The area of the pizza is calculated with the formula: Area = π r2
Note: The π is pi which is equal to 3.14159.The r is the radius of the pizza. Divide the diameter
by 2 to get the radius.
Form:
The application should be done form-based. You may design your own form. It must have the following:
 a label indicating that it is Joe’s Pizza Palace
 a field with label to enter the size (diameter) of the pizza
 a field with label to display the number of slices
 buttons to calculate the number of slices and to exit the application
Output:
Use the following test data to determine if the application is calculating properly:
Diameter of Pizza Number of Slices
22 inches 27
15 inches 13
12 inches 8
Requirements:
 Name the project Pizza.
 Be sure to include your name included in a comment
 No credit is given for a program that will not execute.
 All rules of academic integrity should be applied as stated in the syllabus.
 Submit the zipped project into Moodle.


I have errors saying "With Held " events

WHAT IS WRONG WITH what I HAVE

Code:

---

    Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles button3.Click
        ' End the application
        End
    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        ' Clear the Text Box and lblSlices
        txtDiameter.Clear()
        lblSlices.Text = ""
        ' Return the focus to txtDiameter
        txtDiameter.Focus()
    End Sub
    Private Sub btnCalculate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCalculate.Click
        Dim Slices As Single
        Dim Diameter As Single
        Dim radius As Single

        Diameter = Val(txtDiameter.Text)
        radius = Val(Diameter) \ 2
        Slices = 3.14159 * radius ^ 2 \ 14.125
        lblSlices.Text = FormatNumber(Slices, 0)
    End Sub

    Private Sub lblSlices_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles lblSlices.Click
    End Sub

    Private Function lblSlices() As Object
        Throw New NotImplementedException
    End Function

    Private Function txtDiameter() As Object
        Throw New NotImplementedException
    End Function


End Class

---

this works:

vb Code:

Public Class Form1
 
    Private Sub btnCalculate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCalculate.Click
        If cboDiameter.SelectedIndex > -1 Then
            Dim radius As Double = CDbl(cboDiameter.Text) / 2
            Dim area As Double = Math.PI * (radius ^ 2)
            Dim slices As Integer = CInt(area / 14.125)
            If slices * 14.125 > area Then slices -= 1
            lblSlices.Text = slices.ToString
        End If
    End Sub
 
End Class

Ok I have used what you have and it says 1 error,


Error 1 Handles clause requires a WithEvents variable defined in the containing type or one of its base types.

What do you do with this?

eventHandlers (usually) require a handles clause... i.e.

Code:

---

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

---

the highlighted part is the handles clause