อยากสอบถามจะใช้ JavaScript รับค่าจาก PHP มาแสดงอย่างไรครับ

<?php
$host = 'localhost';
$username = 'root';
$password = '1234';
$data = 'dwbuncee';
$objConnect = mysql_connect($host,$username,$password) or die("MySQL Connect Faied : Error :".mysql_error());
$conDB = mysql_select_db($data) or die("เข้าไม่ได้".mysql_error());
///////////////////////////////////////////////////////////////////
require_once('C:\wamp\www\e_learning\config.php');
	$r=$USER->username;
	//echo "val=$r";
//*************************************************************//
$myid = ($_REQUEST['my_id']);
//$myUser = ($_REQUEST['user_id']);
$myCourse = ($_REQUEST['my_course']);
$myNoCourse = ($_REQUEST['my_noCourse']);
$myChapter = ($_REQUEST['my_chapter']);
//************************************************************//
$result = mysql_query("SELECT MAX(page) AS HighestPrice FROM cpta_action_student WHERE id_card = '$myid' AND userid = '$r' AND course_id = '$myCourse' AND no_course_id = '$myNoCourse' AND chapter = '$myChapter'");
$obj = mysql_fetch_object($result);
echo "myLastPage=$obj->HighestPrice";
//************************************************************//
mysql_close($objConnect);
?>