useless triv 49: how can you tell when a gorilla is angry? it _____?

Questions

What piano man used to play for Bette Middler and then went on to his own career and made Hits like 'Mandy' and 'Copacabana'?

Active volcano in the Philippines, in the central part of Luzon?

The application of science to law?

He produced the Beatles 'Sgt. Peppers Lonely Hearts Club Band'?

Apparatus that converts molecules into ions and then separates the ions according to their mass-to-charge ratio?