Inserting silence at the end of a .wav file

I’m a composer who is submitting audio files of my music in a grant application. I have a number of sound files of examples taken from a long orchestra piece. I’d like to insert the standard 2" of silence between the sound files because they are taken from different places in the composition and not meant to be heard as continuous music. How can I easily do this? Any help will be sincerely appreciated. Thank you!

If you intend to put them on a CD, most CD burning applications automatically insert 2 seconds silence between tracks by default.

I wish I could put all the files on a CD, but they require the musical examples to be sent via the Internet. I’ll use