Im trying to figure out/understand about multiple RETURN functions. But, I cant execute my function.

Code:

function SqFeetToSqMeters(sqFeet)
{
var sqMeters;
sqMeters = sqFeet/10.764;
return sqMeters;
}
function PoundsToKilograms(pounds)
{
var kg;
kg = pounds/2.205;
return kg;
}
//
function CentimetersToInches(cm)
{ var inches;
inches = cm / 2.54;
return inches; }
function HEIGHT(surface, weight)
{var surface = 'sqMeter';
var weight = 'kg';
height = Math.pow(surface, 2) * 3600) / weight);
return height;
}
function FINDHEIGHT()
{
var surface, weight, height;
surface= parseFloat(document.getElementById('SBox').value);
weight = parseFloat(document.getElementById('WBox').value);
height= Math.round(HEIGHT(surface,weight));
document.getElementById('HBox').value = height;
var str1='Your Height is ';
document.getElementById('outputDiv').innerHTML= str1.concat(height);
}
</script>
</head>
<body>
<h2>Using the Mosteller formula to calculate the height from the body Surface and Weight</h2>
<p>
surface: <input type="text" id="SBox" size=4 value=19.45> sq ft.<br>
weight: <input type="text" id="WBox" size=4 value=150> pounds<br>
height(calculated): <input type="text" id="HBox" size=4 value=0> inches<br>
<input type="button" value="calculate the height" onclick="FINDHEIGHT();">
</p>
<hr>
<div id="outputDiv"></div>
</body>
</html>
</html>