What does the keyboard shortcut "ctrl+z" do?

I'm taking a class on how to make a movie, and it offers some apps that would be in the process. the thing is, i don't have any of those ha. if you have any tips on some apps i could use, that would be awesome. i don't have an iphone, so don't suggest any apps like imovie. i know that this is a weird question, but it would be super for me. : )

As with any small island country, cuba has fewer natural resources than countries such as brazil. this affects their economy in that cuba a) exports only manufactured products. b) exports more products than it imports.. c) must import more products than it exports. d) has imposed trade barriers against the united states.

Font size, font style, and are all aspects of character formatting.