function hidealldropdowns() {
	for(i=0;i<document.forms.length;i++) {
     	for(j=0;j<document.forms[i].elements.length;j++) {	
			if(document.forms[i].elements[j].type=="select-one") {
				document.forms[i].elements[j].style.visibility="hidden";
			}
		}
	}
}

function showalldropdowns() {
	for(i=0;i<document.forms.length;i++) {
     	for(j=0;j<document.forms[i].elements.length;j++) {	
			if(document.forms[i].elements[j].type=="select-one") {
				document.forms[i].elements[j].style.visibility="visible";
			}
		}
	}
}