function toggle_visibility(id) {
       		var e = document.getElementById(id);
       		if(e.style.display == 'block')
          		e.style.display = 'none';
       		else
          		e.style.display = 'block';
    	}

	function Check(){
		if(document.theForm.Check_all.checked==true){
			document.getElementById('maxcheck1').checked = true ;
			document.getElementById('maxcheck2').checked = true ;
			document.getElementById('maxcheck3').checked = true ;
                        document.getElementById('maxcheck4').checked = true ;
                        document.getElementById('maxcheck5').checked = true ;
                        document.getElementById('maxcheck6').checked = true ;
		}else{
			document.getElementById('maxcheck1').checked = false ;
                        document.getElementById('maxcheck2').checked = false ;
			document.getElementById('maxcheck3').checked = false ;
                        document.getElementById('maxcheck4').checked = false ;
                        document.getElementById('maxcheck5').checked = false ;
                        document.getElementById('maxcheck6').checked = false ;
		}
	}

	function CheckStudents(){
                if(document.theForm.Check_stu.checked==true){
                                document.getElementById('maxcheck3').checked = true ;
				document.getElementById('maxcheck4').checked = true ;
				document.getElementById('maxcheck5').checked = true ;
				document.getElementById('maxcheck6').checked = true ;
                }else{
			  	document.getElementById('maxcheck3').checked = false ;
                                document.getElementById('maxcheck4').checked = false ;
                                document.getElementById('maxcheck5').checked = false ;
                                document.getElementById('maxcheck6').checked = false ;
                }
        }
	
	function UnCheck(id){
		if(id == 'maxcheck1' || id=='maxcheck2'){
			document.theForm.Check_all.checked=false;
		}
		else{
                        document.theForm.Check_all.checked=false;
			document.theForm.Check_stu.checked=false;
                }
	}