Imports System

Public Module Module1

    Public Sub Main()

        Dim bill,units as Integer

        Console.WriteLine("Please enter your units")

        units = console.ReadLine()

        if units >= 0 and units <= 100 then

            bill = units*10

        else if units > 100 and units < 301 then

                bill = units*20

            else if units > 300 then

                    bill = units*30

                else

                    console.writeline("Not valid")

End if

                    console.writeline("Your bill is" & bill)

    End Sub

End Module