var activeTab;
var url = location.href.split('/').pop();
if ( url.indexOf('activities') < 0 ) {
	activeTab = 'tab3';	
}
else {
	activeTab = 'tab5';
}

function show_div(div_id) {
    // hide all the divs
	document.getElementById(activeTab).style.display = 'none';

    // show the requested div
    document.getElementById(div_id).style.display = 'block';
	
	activeTab = div_id;
}