function doPreload() {
	var the_images = new Array('_images/bu_benefits-over.png', '_images/bu_facility-over.png', '_images/bu_classes-over.png', '_images/bu_trainers-over.png');
	preloadImages(the_images);
}

function preloadImages(the_images_array) {
	for(loop = 0; loop < the_images_array.length; loop++)
	{
   		var an_image = new Image();
		an_image.src = the_images_array[loop];
	}
}


function swapimageOver(image) {
	var imgName= "_images/bu_" + image ;
	var source = document.getElementById(image) ;
	source.src = imgName + "-over.png" ;
}

function swapimageOut(image) {
	var imgName= "_images/bu_" + image ;
	var source = document.getElementById(image) ;
	source.src = imgName + ".png" ;
}