if (document.getElementById) { window.onload = swap };

function swap() {
var numfindings=9;
rndfind = new Array("a001","a002","a003","a004","a005","a006","a007","a008","a009"); 
x=(Math.floor(Math.random()*numfindings));
randomfinding=(rndfind[x]);
document.getElementById(randomfinding).style.display = "block"; 
}