// set up images
var banner = new Array() // don't change this
banner[0] = 'images/bannerpics/bannerpic01.jpg'
banner[1] = 'images/bannerpics/bannerpic02.jpg'
banner[2] = 'images/bannerpics/bannerpic03.jpg'
banner[3] = 'images/ibannerpics/bannerpic04.jpg'
banner[4] = 'images/bannerpics/bannerpic05.jpg'
// don't change anything below!
var j = 0
var p = banner.length;
var preBuffer = new Array()
for (i = 0; i < p; i++){
   preBuffer[i] = new Image()
   preBuffer[i].src = banner[i]
}
var whichImage = Math.round(Math.random()*(p-1));
function bannerImage(){
document.write('<img src="'+banner[whichImage]+'">');
}