MS-DOS Prompt command help?

[Inexistence]

Hi, I've been experimenting with the MS-DOS Command prompt and was wondering if there's a way to allow me to do the following:

I can already do part of it, which is simply opening 3 pages at once, but how do I manage to close these without manually clicking them?

Say the address is http://www.google.com, I have

@echo off
start http://www.google.com
start http://www.google.com
start http://www.google.com

Anyone know how I can close these by putting it in the batch file?

My default browser is FF if that matters.