// JavaScript Document
function validate(form) {
// Checking if at least one period button is selected. Or not.
if (document.quiz1.q[0].checked ){

setVisibility('sub1', 'inline');
setVisibility('sub2','none');
}else{
setVisibility('sub2', 'inline');
setVisibility('sub1','none');
}
}

function setVisibility(id, visibility) {
document.getElementById(id).style.display = visibility;
}