function checkEntries() {

	var name  = document.getElementById('name');
	var phone = document.getElementById('phone');
	var email = document.getElementById('email');

	if(name.value == '') {
		alert('Name field cannot be empty!');
		return false;
	}
	
	if(phone.value == '') {
		alert('Phone field cannot be empty!');
		return false;
	}
	
	if(email.value == '') {
		alert('Email field cannot be empty!');
		return false
	}

	return true;
}

function openwindow(mypage,myname,w,h,features) {
  if(screen.width){
  var winl = (screen.width-w);
  var wint = (screen.height-h);
  }else{winl = 0;wint =0;}
  if (winl < 0) winl = 0;
  if (wint < 0) wint = 0;
  var settings = 'height=' + h + ',';
  settings += 'width=' + w + ',';
  settings += 'top=' + wint + ',';
  settings += 'left=' + winl + ',';
  settings += 'resizable=yes,scrollbars=yes,left=140,top=20,';
  win = window.open(mypage,myname,settings);
  win.window.focus();
}