Course he will. It has its own file type for editing and such, so you can open the file to edit more.
But you can export out as Wave, and also MP3.
To export out MP3, you'll need the Lame.dll though which can easily be found here:
You''ll after downloading it and placing it somewhere, have to go into File, Prefrences within Audicity.
Within the File Formats tab, they'll then be an option to Find Library. You simply find the Lame.dll file you downloaded.
You then select bitrate and such to save to, and you then have MP3 exportation from File , Export as MP3