I have a cron job running a PHP script every five minutes; the PHP script executes two bash commands at the end of the script. I know the script is running due to a log file it appends to. When I run the PHP script manually via the Ubuntu Gnome Terminal both bash commands execute flawlessly; however when the PHP script is triggered via cron, the two bash commands are not ran. Any ideas?

```
$command = 'notify-send "' . count($infoleakPosts) . '  New Posts."';
`$command`;

$command = 'firefox http://example.com';
`$command`;

*/1 * * * * php /home/andrew/grab.php USERNAME PASSWORD # JOB_ID_1

```