a0=new Image;a0.src="img/1a.gif"; 
a1=new Image;a1.src="img/2a.gif"; 
a2=new Image;a2.src="img/3a.gif"; 
a3=new Image;a3.src="img/4a.gif"; 
a4=new Image;a4.src="img/5a.gif"; 
a5=new Image;a5.src="img/6a.gif";
a6=new Image;a6.src="img/7a.gif"; 
a7=new Image;a7.src="img/8a.gif";