function changeTab(imgName, fileName)
{
	eval(imgName+".src ='"+fileName+"';");
}

function showTab(fm)
{
	
	var f = document.all;
	if (fm==1)
	{
	f.tb1.style.display = "" ;
	f.tb2.style.display = "none" ;
	f.tb3.style.display = "none" ;
	f.tb4.style.display = "none" ;
	}
	else if (fm==2)
	{
	f.tb1.style.display = "none" ;
	f.tb2.style.display = "" ;
	f.tb3.style.display = "none" ;
	f.tb4.style.display = "none" ;
	}
	else if (fm==3)
	{
	f.tb1.style.display = "none" ;
	f.tb2.style.display = "none" ;
	f.tb3.style.display = "" ;
	f.tb4.style.display = "none" ;
	}
	else if (fm==4)
	{
	f.tb1.style.display = "none" ;
	f.tb2.style.display = "none" ;
	f.tb3.style.display = "none" ;
	f.tb4.style.display = "" ;
	}

}