function imageEX(){
var s = Math.floor(Math.random()*3)
if ( s ==  0 ) document.write('<img src="./img/main01.jpg" alt="" width="600" height="202" />');
if ( s ==  1 ) document.write('<img src="./img/main02.jpg" alt="" width="600" height="202" />');
if ( s ==  2 ) document.write('<img src="./img/main03.jpg" alt="" width="600" height="202" />');
}
//-->