Display the cities in the country and Image

Bease Upon you

I have two quesion

the first quesion

I Have two table one for country and the second for cities and i have two combo box one to take the country from the country table and the second to take the cities from cities table

the combobox for countries it works ok but i want when the user select the country from the first combobox the second combobox only show the cities in the country in the first combobox is there events like onchange or onclick if yes where shall i put it please give me the solution with example

and this the code what i have witen

<html>

<body>

<?php

$n=mysql_connect("localhost","root","");

$m=mysql_db_query("data2","select * from country");

echo "<select name=code_country>";

while ($nn=mysql_fetch_array($m)

{

echo "<option value=.$nn['country_id].>.$nn['name'].</option>";

}

echo "</select>";

$code_country=$_GET['Code_country'];

if (empty($code_country))

$sql="select * from city where country_id=(select Country_id from country limit 1,1)";

else

$sql="select * from city where country_id='$code_country' ";

echo '<select name="code_city">';

$query=mysql_query($sql) or die (mysql_error());

while ($data=mysql_fetch_array($query)

{

echo "<option value='.$data['city_id'].'>'.$data['name'].'</option>";

}

echo '</select>';

?>

</body>

</html>

the second quesion

this quesion about image and picture

i want to brows the pictures in any folder and to show the picture in the wep page is there any image box or picture to display the picture like visual baisc or i use the table

the code what i have writen

<input type =file name img>

<input type=submit>

in this page the user can select the picture but i want to display the picture in the page

please help me as i need it urgently

Allah bless You