function show_hide(i) {
	if (document.getElementById(i).style.display == 'block') {
		//document.getElementById(i).style.display = 'none';
	} else {
		document.getElementById(i).style.display = 'block';
		//document.getElementById('email').value = '';
	}
}

function isEmailAddress (string) {
    var addressPattern = /^\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+$/;
    return addressPattern.test(string);
}
function validateUSZip(strValue) {
	var objRegExp  = /(^\d{5}$)|(^\d{5}-\d{4}$)/;
	return objRegExp.test(strValue);
}
function notEmptyStr(strValue) {
	var objRegExp  = /[^ \t\v\f\n\r]$/;
	return objRegExp.test(strValue);
}
function validateContactForm(f) {
	var err ="";
	var requiredArr = Array("topic", "first_name", "last_name", "message");
	var requiredArrName = Array("topic", "first name", "last name", "question or comment");
	if (notEmptyStr(f.reason_for_contact.value)==false) {
		err+="Please answer 'What are you contacting us about?'"+"\r\n";
	} 
	for (var i=0; i<requiredArr.length; i++) {
		var curInput = eval("f."+requiredArr[i]);
		if(notEmptyStr(curInput.value)==false) {
			err+=("Please provide a "+requiredArrName[i]+"\r\n");
		}
	}
	if (isEmailAddress(f.email.value)==false) {
		err+="Please provide a valid email address"+"\r\n";
	} 
	if (notEmptyStr(f.where_did_you_hear.value)==false) {
		err+="Please answer 'Where did you hear about us?'"+"\r\n";
	} 
	if (err!="") { 
		alert(err);
		return false;
	} else {
            f.required.value="1";
            return true;
        }
}