No idea even what Is It Me? is.
Say It's Not True is a piece of piss and you should be able to figure it out on your own.
If I remember, it's in C, so basically uses C, Am, F and G. I think that may be it in fact, although I can't really remember how the song goes.
Gullibility and credulity are considered undesirable qualities in every department of human life -- except religion.