Visual basic Comand "3" > Rata-rata Nilai dan Grade

Private Sub Command1_Click()
'Deklarasi Variabel
Dim tik, bio, kimia, pkn, agama, total, rata As Double
Dim Grade As String
'Deklarasi Nilai
tik = Text3.Text
bio = Text4.Text
kimia = Text5.Text
pkn = Text6.Text
agama = Text7.Text
'Perhitungan Total nilai
total = Val(tik) + (bio) + (kimia) + (pkn) + (agama)

'Perhitungan rata-rata nilai
rata = total / 5

'penentuan Grade
If rata <= 59.99 Then
Grade = "D"

ElseIf rata <= 74.99 Then
Grade = "C"

ElseIf rata <= 84.99 Then
Grade = "B"

ElseIf rata <= 100 Then
Grade = "A"

End If
'Deklarasi Keluaran Total Nilai,Rata-rata dan grade
Text8.Text = total
Text9.Text = rata
Text10.Text = Grade

End Sub

Private Sub Command2_Click()
'Membersihkan isi Textbox
Text1.Text = ""
Text2.Text = ""
Text3.Text = ""
Text4.Text = ""
Text5.Text = ""
Text6.Text = ""
Text7.Text = ""
End Sub

Private Sub Command3_Click()
OK = MsgBox("anda yakin?", vbYesNo + vbExclamation, "konfirmasi")
If OK = vbYes Then
        Unload Me
End If
End Sub

Private Sub Form_Load()

End Sub