function subtbldisp(a)
{
 if(a=="1")
  {
		main_tbl1.style.display='none';
  whatsnew_tbl2.style.display='';
  signup_tbl3.style.display='none';
  dontknow_tbl4.style.display='none';
  howto_tbl5.style.display='none';
		//alert('Sai Ram');
		//window.Image107.src='images2/whats_bttroll.jpg';
		//alert('Ram Sai');
}

if(a=="2")
  {
		main_tbl1.style.display='none';
  whatsnew_tbl2.style.display='none';
  signup_tbl3.style.display='';
  dontknow_tbl4.style.display='none';
  howto_tbl5.style.display='none';
 	}
 if(a=="3")
  {
		main_tbl1.style.display='none';
  whatsnew_tbl2.style.display='none';
  signup_tbl3.style.display='none';
  dontknow_tbl4.style.display='';
  howto_tbl5.style.display='none';
 	}
 if(a=="4")
  {
		main_tbl1.style.display='none';
  whatsnew_tbl2.style.display='none';
  signup_tbl3.style.display='none';
  dontknow_tbl4.style.display='none';
  howto_tbl5.style.display='';
 	}
 if(a=="5")
  {
		main_tbl1.style.display='';
  whatsnew_tbl2.style.display='none';
  signup_tbl3.style.display='none';
  dontknow_tbl4.style.display='none';
  howto_tbl5.style.display='none';
 	}
}