function setHeight(){
	h1=document.getElementById("table1").clientHeight;
	h2=document.getElementById("table2").clientHeight;
	h3=document.getElementById("table3").clientHeight;
	objTable=document.getElementById("maintable");
	h=objTable.clientHeight;
	var allh=h*10/9;
	objTable.height=allh-h1-h2-h3;
}