9.3

Code for 9.3 task below:


Public Class Form1

    Private Sub btnCalcInterest_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCalcInterest.Click
        Dim Interest, AmountInvested As Decimal
        Dim RateOfInterest As Single
        Dim Years As Short
        AmountInvested = txtamountinvested.text
        RateOfInterest = txtInterestRate.Text
        Years = txtYears.Text
        Interest = CalculateInterest(AmountInvested, RateOfInterest, Years)
        lblinterestrate.Text = Format(Interest, "Currency")

    End Sub
    Function CalculateInterest(ByVal Principal As Decimal, ByVal InterestRate As Single, ByVal numberYears As Short) As Decimal
        Dim Interest As Decimal
        Dim Year As Short
        Interest = 0
        For Year = 1 To numberYears
            Interest = Interest + ((Principal + Interest) * InterestRate / 100)
        Next Year
        Return Interest
        CalculateInterest = Interest
    End Function


End Class