home_on = new Image();
home_off= new Image();

home_on.src="images/home_on.gif"
home_off.src="images/home_off.gif"

tests_on = new Image();
tests_off= new Image();

tests_on.src="images/tests_on.gif"
tests_off.src="images/tests_off.gif"


cost_on = new Image();
cost_off= new Image();

cost_on.src="images/cost_on.gif"
cost_off.src="images/cost_off.gif"



contact_on = new Image();
contact_off= new Image();

contact_on.src="images/contact_on.gif"
contact_off.src="images/contact_off.gif"



ppij_on = new Image();
ppij_off= new Image();

ppij_on.src="images/ppij_on.gif"
ppij_off.src="images/ppij_off.gif"


dvi_on = new Image();
dvi_off= new Image();

dvi_on.src="images/dvi_on.gif"
dvi_off.src="images/dvi_off.gif"




jto_on = new Image();
jto_off= new Image();

jto_on.src="images/jto_on.gif"
jto_off.src="images/jto_off.gif"



ppi_on = new Image();
ppi_off= new Image();

ppi_on.src="images/ppi_on.gif"
ppi_off.src="images/ppi_off.gif"



ato_on = new Image();
ato_off= new Image();

ato_on.src="images/ato_on.gif"
ato_off.src="images/ato_off.gif"

var hidden=true;

function show(){
	document.getElementById('dropdown').style.visibility='visible';
	hidden=false;
}
function hide(){
	hidden=true;
	setTimeout("hideit()",280)

}

function hideit(){
	if (hidden) {
		document.getElementById('dropdown').style.visibility='hidden';
	}

}


function rollOver(id) {
	
	if (document.images) {
		button=eval ( id+"_on.src")
		document.getElementById(id).src=button;
	
	}
	
}


function rollOut(id) {
	
	if (document.images) {
		button=eval ( id+"_off.src")
		document.getElementById(id).src=button;
	
	}
	
}