Actually Fixed Cylinder Calc

Program PracticeCalc;

Uses
    crt;

Var
    ResponseA:string;
    ResponseB:string;
    SurfaceArea:Real;
    Volume:Real;
    Height:Real;
    Radius:Real;

Begin
    ResponseA:='';
    ResponseB:='';
    Volume:=0;
    Height:=0;
    Radius:=0;

    writeln('Would you like to calculate the volume of a cylinder? (Yes/No)');
    readln(ResponseA);
    ResponseA:=UpCase(ResponseA);

    while((ResponseA[1]<>'Y')and(ResponseA[1]<>'N')) do
        Begin
            writeln('Please enter a valid response');
            readln(ResponseA);
            ResponseA:=UpCase(ResponseA);
        End;

    If (ResponseA[1]='Y') then
        Begin
            writeln('Please enter a value for height.');
            readln(Height);
            writeln('Please enter a value for radius.');
            readln(Radius);
            Volume:=sqr(Radius)*(PI)*(Height);
            writeln('The Volume is ', Volume:0:2);
            readln();
        End;

    clrscr;

    writeln('Would you like to calculate the surface area of a cylinder? (Yes/No)');
    readln(ResponseB);
    ResponseB:=UpCase(ResponseB);

    while((ResponseB[1]<>'Y')and(ResponseB[1]<>'N')) do
        Begin
            writeln('Please enter a valid response');
            readln(ResponseB);
            ResponseB:=UpCase(ResponseB);
        End;

    If (ResponseB[1]='Y') then
        Begin
            clrscr;
            writeln('Please enter a value for height.');
            readln(Height);
            writeln('Please enter a value for radius');
            readln(Radius);
            SurfaceArea:=((2*PI*Radius*Height)+(2*PI*sqr(Radius)));
            writeln('The Surface Area is ', SurfaceArea:0:2);
            readln();
        End;

    clrscr;

    If (ResponseA[1]='Y') then
        writeln('Volume: ', Volume:0:2);
    If (ResponseB[1]='Y') then
        writeln('Surface area: ', SurfaceArea:0:2);

    readln();
End.