function PTLamount(d1){
			
		var WrkTable=document.getElementById("PTLamountText");
		WrkTable.style.visibility="visible";	
		
		var amountl = 0;
		
	   amountl = getAmount2(d1);
      
		WrkTable.value = "You Will Need  " + amountl +  "  Lbs. Of Glass " ;
	
	}
	
	function getAmount2(d1) {
		
		var amountl=0;
		var basel =0;

        dn = d1 - 0;

		basel = (dn * dn * 2) / 231;
		basel = basel * .8;
		amountl = (Math.round(basel * 12));
		return amountl;
	}