function get_random_num(num_elements){
	// number from 1 . . . (num_elements)
	var i = Math.round((num_elements-1)*Math.random()) + 1;
	if (i < 10){
		i= '0' + i;
	}
	return i;
}

function get_topright_img(){
	document.write('<a href="imagerevo.html"><img src="images/rt_col_' + get_random_num(2) + '.jpg" id="rightcol_topimg" alt="right column image" /></a>');
}
function get_leftcol_img(){
	document.write('<a href="imagerevo.html"><img src="images/left_col_' + get_random_num(5) + '.jpg" id="leftcol_img" alt="left column image" /></a>');
}
function get_midcol_img(){
	document.write('<a href="imagerevo.html"><img src="images/mid_col_' + get_random_num(5) + '.jpg" alt="middle column image" width="500" height="80" style="border:0; padding:0;" /></a>');
}