function col_expand1() {	  
			 document.getElementById("expand1").style.display = 'block';
			 document.getElementById("expand2").style.display = 'none';
			 document.getElementById("expand3").style.display = 'none';
			 document.getElementById("expand4").style.display = 'none';		 
			 
			 
		} 
	function col_expand2() {
			 document.getElementById("expand2").style.display = 'block';
			 document.getElementById("expand1").style.display = 'none';
			 document.getElementById("expand3").style.display = 'none';
			 document.getElementById("expand4").style.display = 'none';		 
			 
		} 
	function col_expand3() { 
			 document.getElementById("expand3").style.display = 'block';
			 document.getElementById("expand2").style.display = 'none';
			 document.getElementById("expand1").style.display = 'none';
			 document.getElementById("expand4").style.display = 'none';		 
		} 
	function col_expand4() {	  
			 document.getElementById("expand4").style.display = 'block';
			 document.getElementById("expand2").style.display = 'none';
			 document.getElementById("expand3").style.display = 'none';
			 document.getElementById("expand1").style.display = 'none';		 
		}