Android music file format?

Hello :) I'm putting sounds on my game. But, I don't know what format to use, I've been searching and read that I should use Wav files for sounds effects and mp3 for long music. Yes, mp3 is good because of its compression BUT i also read that when you published your game and sold 5000 copies of it, with mp3 file in it, you will pay $2500 - $3750. And I'm afraid of that (lol, and is that true?). And if I need a wav file, is it "Wav 32-bit float PCM" or "Wav signed 16-bit PCM" ? Thank you very much in advance!

Ps. sorry, just afraid of licensing issues xD