function ropic() {
number = Math.floor(Math.random()*4)
if (number==0)
document.write('<img src="images/top_home_1.jpg" alt="Home" width="701" height="225">')
if (number==1)
document.write('<img src="images/top_home_5.jpg" alt="Home" width="701" height="225">')
if (number==2)
document.write('<img src="images/top_home_6.jpg" alt="Home" width="701" height="225">')
if (number==3)
document.write('<img src="images/top_home_7.jpg" alt="Home" width="701" height="225">')
}