function getFirstParam(){
	//this gets the survey height from the url of the iFrame hidden inside the survey.
	//technically, it gets the first parameter from the url of the calling window
	var pair = window.location.search.substring( 1 );
	var parts = pair.split( '=' );
	var param = parseInt( parts[1] );
	return param;
}

function loadHiddenIframe(path) {
	//this gets the height of the survey. 
	//technically, it gets the height of the calling window.
	var height = Math.max( document.body.offsetHeight, document.body.scrollHeight );

	//we add 50 pixels, to make the frame tall enough for the gizmo advertising link at the bottom of the survey
	height = height + 50;

	//this loads the hidden page into the iFrame hidden inside the survey, with height as a url parameter.
	var iframe = document.getElementById( 'HiddenIframe' );
	iframe.src = path + '?height=' + height;
}