a1=new Image
a1.src="homebutton.png"
a2=new Image
a2.src="homebutton1.png"
b1=new Image
b1.src="extendedstaybutton.png"
b2=new Image
b2.src="extendedstaybutton1.png"
c1=new Image
c1.src="annualpoliciesbutton.png"
c2=new Image
c2.src="annualpoliciesbutton1.png"
d1=new Image
d1.src="policywordingbutton.png"
d2=new Image
d2.src="policywordingbutton1.png"
e1=new Image
e1.src="contactusbutton.png"
e2=new Image
e2.src="contactusbutton1.png"
f1=new Image
f1.src="travelcovbutton.png"
f2=new Image
f2.src="travelcovbutton1.png"
g1=new Image
g1.src="singletripbutton.png"
g2=new Image
g2.src="singletripbutton1.png"

function filter(imagename,objectsrc){
if (document.images)
document.images[imagename].src=eval(objectsrc+".src")
}