if(document.images)
{
var b_hista=new Image()
b_hista.src="graphics/b_hista.gif"
var b_histn=new Image()
b_histn.src="graphics/b_histn.gif"
var b_contacta=new Image()
b_contacta.src="graphics/b_contacta.gif"
var b_contactn=new Image()
b_contactn.src="graphics/b_contactn.gif"
var b_dira=new Image()
b_dira.src="graphics/b_dira.gif"
var b_dirn=new Image()
b_dirn.src="graphics/b_dirn.gif"
var b_newsa=new Image()
b_newsa.src="graphics/b_newsa.gif"
var b_newsn=new Image()
b_newsn.src="graphics/b_newsn.gif"
var b_porta=new Image()
b_porta.src="graphics/b_porta.gif"
var b_portn=new Image()
b_portn.src="graphics/b_portn.gif"
var b_serva=new Image()
b_serva.src="graphics/b_serva.gif"
var b_servn=new Image()
b_servn.src="graphics/b_servn.gif"
var b_creda=new Image()
b_creda.src="graphics/b_creda.gif"
var b_credn=new Image()
b_credn.src="graphics/b_credn.gif"
}
function act(imgName){if(document.images)
document[imgName].src=eval(imgName+'a.src')
}
function inact(imgName){if(document.images)
document[imgName].src=eval(imgName+'n.src')
}