inserting array values to mysql with php on front end

[hema rajeev]

$services_name=$_POST['services_name'];
$man_hour=$_POST['man_hour'];
$rate=$_POST['rate'];
$service_tax=$_POST['service_tax'];
$total=$_POST['total'];

$limit = count($services_name);
for($i=0;$i<$limit;$i++) {
$services_name[$i] = mysql_real_escape_string($services_name[$i]);
$man_hour[$i] = mysql_real_escape_string($man_hour[$i]);
$rate[$i] = mysql_real_escape_string($rate[$i]);
$service_tax[$i] = mysql_real_escape_string($service_tax[$i]);
$total[$i] = mysql_real_escape_string($total[$i]);


if($_POST['submit']=="Submit")
{
$qry="INSERT INTO invoice(`services_name`,`man_hour`,`rate`,`service_tax`,`total`) VALUES

('".$services_name[$i]."','".$man_hour[$i]."','".$rate[$i]."','".$service_tax[$i]."','".$total[$i]."')";
mysql_db_query($db,$qry)$change=mysql_insert_id();;


}
}
thi s my mysql code...
i am struck up with a mysql code where i need to enter array values to mysql.....now none of the data is entering to the db.