Which characteristic of a vibrating body determines the (a) loudness (b) pitch of the sound produced by it?

-- The loudness of the vibration is determined by its amplitude.

-- The pitch of the vibration is determined by its frequency.

-- The amplitude and frequency of the vibration are determined by the material characteristics of the body that's vibrating, and by how much energy is used to start the vibrations.

this a false

explanation:

a coal burning power plant