Fact 1: Afirecracker converts chemical energy into sound.

Fact 2: Sound waves are vibrations in matter.

Given the two facts above, answer the question "a firecracker converts chemical energy into what?" with the following options: 
- kinetic energy
 - electromagnetic energy
 - An object is seen
 - vibrations in matter
 - objects that have mass
 - harmful substances
 - The bending of a ray of light
 - Loud noises


 

    vibrations in matter     