Perform the following steps:

1. Enter two integers into the form below.
2. Click the form's submit button.
3. View the resulting display (of course).
4. But also look carefully at the contents of the
   display page's address bar. This time, because
   we are using the POST protocol for passing
   the form data to the PHP script for processing,
   nothing but the plain URL of the processing
   script appears in the address bar.