how to call two function in JS

<pre lang="cs">function formValidator(){
    // Make quick references to our fields
    var Company = document.getElementById('Company');
    var Designation = document.getElementById('Designation');
    var FirstName = document.getElementById('First Name');
    var LastName = document.getElementById('Last Name');
    var Phone = document.getElementById('Phone');
    var Email = document.getElementById('Email');
    var Website = document.getElementById('Website');
    var Industry = document.getElementById('Industry');
    var NoofEmployees = document.getElementById('No of Employees');
    // Check each input in the order that it appears in the form!
    if(isAlphanumeric(Company, "Please enter company name") || notEmpty(Company,"Please enter company name"){
        if(isAlphabet(Designation, "Please enter title")){
            if(isAlphabet(FirstName, "Please enter first name")){
                if(isAlphabet(LastName, "Please enter last name")){
                    if(isAlphanumeric(Phone, "Please enter phone number")){
                        if(emailValidator(Email,"Please enter a valid email address")){
                            if(isValidURL(Website, "Please enter a valid URL address")){
                                if(madeSelection(Industry, "Industry is not selected")){
                                    if(isNumeric(NoofEmployees, "Please enter number of employees")){
                                        return true;
                                    }
                                }
                            }
                        }
                    }
                }
            }
        }
    }

    return false;
}
function notEmpty(elem, helperMsg){
    if(elem.value.length == 0){
        alert(helperMsg);
        elem.focus(); // set the focus to this input
        return false;
    }
    return true;
}
function isNumeric(elem, helperMsg){
    var numericExpression = /^[0-9]+$/;
    if(elem.value.match(numericExpression)){
        return true;
    }else{
        alert(helperMsg);
        elem.focus();
        return false;
    }
}
function isValidURL(url,helperMsg){
    var urlExp = /^(([\w]+:)?\/\/)?(([\d\w]|%[a-fA-f\d]{2,2})+(:([\d\w]|%[a-fA-f\d]{2,2})+)?@)?([\d\w][-\d\w]{0,253}[\d\w]\.)+[\w]{2,4}(:[\d]+)?(\/([-+_~.\d\w]|%[a-fA-f\d]{2,2})*)*(\?(&?([-+_~.\d\w]|%[a-fA-f\d]{2,2})=?)*)?(#([-+_~.\d\w]|%[a-fA-f\d]{2,2})*)?$/;
    if(elem.value.match(urlExp)){
        return true;
    }else{
        alert(helperMsg);
        elem.focus();
        return false;
    }
}
function isAlphabet(elem, helperMsg){
    var alphaExp = /^[a-zA-Z]+$/;
    if(elem.value.match(alphaExp)){
        return true;
    }else{
        alert(helperMsg);
        elem.focus();
        return false;
    }
}
function isAlphanumeric(elem, helperMsg){
    var alphaExp = /^[0-9a-zA-Z]+$/;
    if(elem.value.match(alphaExp)){
        return true;
    }else{
        alert(helperMsg);
        elem.focus();
        return false;
    }
}
function lengthRestriction(elem, min, max){
    var uInput = elem.value;
    if(uInput.length >= min && uInput.length <= max){
        return true;
    }else{
        alert("Please enter between " +min+ " and " +max+ " characters");
        elem.focus();
        return false;
    }
}
function madeSelection(elem, helperMsg){
    if(elem.value == "-None-"){
        alert(helperMsg);
        elem.focus();
        return false;
    }else{
        return true;
    }
}
function emailValidator(elem, helperMsg){
    var emailExp = /^[\w\-\.\+]+\@[a-zA-Z0-9\.\-]+\.[a-zA-z0-9]{2,4}$/;
    if(elem.value.match(emailExp)){
        return true;
    }else{
        alert(helperMsg);
        elem.focus();
        return false;
    }
}

    function ajaxFunction(){
    var ajaxRequest;  // The variable that makes Ajax possible!
    try{
        // Opera 8.0+, Firefox, Safari
        ajaxRequest = new XMLHttpRequest();
    } catch (e){
        // Internet Explorer Browsers
        try{
            ajaxRequest = new ActiveXObject("Msxml2.XMLHTTP");
        } catch (e) {
            try{
                ajaxRequest = new ActiveXObject("Microsoft.XMLHTTP");
            } catch (e){
                // Something went wrong
                alert("Your browser broke!");
                return false;
            }
        }
    }
    // Create a function that will receive data sent from the server
    ajaxRequest.onreadystatechange = function(){
        if(ajaxRequest.readyState == 4){
            //document.myForm.time.value = ajaxRequest.responseText;
            document.myForm.submit();
        }
    }
    var Company = document.getElementById('Company').value;
    var Email = document.getElementById('Email').value;
    var NoofEmployees = document.getElementById('NoofEmployees').value;
    var queryString = "?Company=" + Company + "&Email=" + Email + "&NoofEmployees=" + NoofEmployees ;
    ajaxRequest.open("GET", "main.php" + queryString, true);
    ajaxRequest.send(null);
}