function bmi()
{
	document.write("<form id=frmBMI>");
	document.write("Weight:<br><input type=text id=weight size=10> kg");
	document.write("<br>");
	document.write("Height:<br><input type=text id=height size=10> m");
	document.write("<br>");
	document.write("<input type=button name=submit value=Calculate BMI onClick=calculatebmi(this.form) >");
	document.write("<br><br>");
	document.write("Your BMI:<br><input type=text id=BMI size=10>");
	document.write("</form>");

}

function calculatebmi(form)
{
	var strWeight=form.weight.value;
	var strHeight=form.height.value;
	var bmi;

	bmi=(strWeight)/(strHeight*strHeight);
	form.BMI.value=bmi.toPrecision(3);

}
bmi();