Imports System

Public Module Module1

    Public Sub Main()

        Dim Total as Decimal 

        Dim Average as Decimal 

        DIm Mark as integer

        Dim Counter as integer 

        Total = 0

        Mark = 0

        Counter = -1

        Console.WriteLine("Enter marks, 999 to finish ")

        Mark = Console.Readline()

    Total = Total + Mark

            If mark = 999 Then

            Average = Total/Counter

        Else

            End If 

        While Mark < 999

            Counter = Counter + 1

        End while 

        Console.WriteLine("The total mark is ", Total)

        Console.WriteLine("The average mark is ", Average)

        Console.Writeline("The number of marks is ", Counter) 

        Console.Readline()

    End Sub

End Module