var currId = 'poll20';  
function show_div(div_id) {  
    if(currId) 
        document.getElementById(currId).style.display = 'none'; 
    document.getElementById(div_id).style.display = 'block'; 
    currId = div_id; 
};  

var currissueId = 'issue1';  
function show_divissue(divissue_id) {  
	if(currissueId)
	document.getElementById(currissueId).style.display = 'none'; 
	document.getElementById(divissue_id).style.display = 'block'; 
	currissueId = divissue_id; 
};  

var trendsId = 'trendsimg1';  
function show_divtrends(divtrends_id) {  
	if(trendsId)
	document.getElementById(trendsId).style.display = 'none'; 
	document.getElementById(divtrends_id).style.display = 'block'; 
	trendsId = divtrends_id; 
};