For problems 1 and 2, the files here are just what are needed for the
notebooks to render correctly. To get all the data, go to the
following link:

https://www.dropbox.com/s/0clmmvwkoy000d4/homework1_data.tgz

For problems 3 and 4, this directory contains all necessary files
(voice.wav and the moon images).  You do not need anything else.