E2314 Call of nonfunction

//---------------------------------------------------------------------------
 
#include <vcl.h>
#pragma hdrstop
 
#include "Unit7.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
#define TR 60
int pw,RandomRange;
int rem = TR;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
    : TForm(Owner)
{
Label2->Caption = IntToStr(TR);
ProgressBar1->Max = TR;
ProgressBar1->Position = TR;
ProgressBar1->Step = 1;
ProgressBar1->Smooth = true;
Randomize() ;
[B]pw = RandomRange(0,999);[/B]
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Timer1Timer(TObject *Sender)
{
rem ;
ProgressBar1->Position--;
Label2->Caption = IntToStr(rem);
if (rem == 0 )
{
Timer1->Enabled = false;
Edit1->Enabled = false;
Button1->Enabled = false;
ShowMessage("К сожалению, Вы не справились с"
" поставленной задачей\п "Секретное" число:" +
IntToStr(pw) );
}
}
//---------------------------------------------------------------------------
void __fastcall TForm1::CheckBox1Click(TObject *Sender)
{
if ( CheckBox1->Checked )
{
ProgressBar1->Step = 1 ;
ProgressBar1->Smooth = true;
}
else
{
ProgressBar1->Step = 6 ;
ProgressBar1->Smooth = false;
}
}
//---------------------------------------------------------------------------
void __fastcall TForm1::isRight(void)
{
if ( StrToInt(Edit1->Text) == pw )
{
Timer1->Enabled = false;
Button1->Enabled = false;
Edit1->Enabled = false;
ShowMessage("Поздравляю!\nВы угадали число за " +
IntToStr(TR - rem)+ " сек");
}
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Edit1KeyPress(TObject *Sender, char &Key)
{
if ( ( Edit1->Text.Length() < 3) &&
((Key >= '0') &&
(Key <= '9')))
return;
if ( Key == VK_RETURN)
{
isRight();
return;
}
if ( Key == VK_BACK) return;
Key = 0;
}
//---------------------------------------------------------------------------
 
void __fastcall TForm1::Edit1Change(TObject *Sender)
{
if ( Edit1->Text.Length() == 3)
Button1->Enabled = true;
else
Button1->Enabled = false;
}
//---------------------------------------------------------------------------
 
void __fastcall TForm1::Button1Click(TObject *Sender)
{
isRight();
}
//---------------------------------------------------------------------------

#include <Math.hpp>

int pw;

pw = RandomRange(0, 1000);