jquery $.get and data return

Hi

I need to send id to script and return array..

I have my first_page.php

Here I have try this

$.get('log.php',{id:'4'},function(data){
alert("Data Loaded: " + data);
});

log.php receive id..

Now, i need GET into first_page.php a result as js array..

How I must prepare this data in log.php and how I can get this on first page ?

Txx