arrImg = new Array ("/images/homepage/background/bg_acrobat_nspire2.jpg", 
										"/images/homepage/background/bg_soccer_nspire2CAS.jpg");		
myNum=Math.floor(arrImg.length * Math.random());	
bgimg='<img src="'+ arrImg[myNum]+ '" border="0" align="absmiddle" width="960" height="449">';

//hide footer horizontal line
document.write("<style type='text/css'>#footer {background-image:none;}</style>");