function validContactUs() {
	var email = document.getElementById("email");
	if(email.value.length==0) {
		alert('Email address cannot be empty.');
		return false;
	} else if (!checkEmail(email.value)) {
		alert('Email address is invalid.');
		return false;
	}
	var name = document.getElementById("name");
	if(name.value.length==0) {
		alert('Name cannot be empty.');
		return false;
	}
	var subject = document.getElementById("subject");
	if(subject.value.length==0) {
		alert('Subject cannot be empty.');
		return false;
	}
	var text = document.getElementById("text");
	if(text.value.length==0) {
		alert('Message cannot be empty.');
		return false;
	}
	return true;	
}