Question

which best describes what happens if two waves meet and build on each other?
constructive interference
destructive interference
reflection
absorption

Explanation:

When two waves meet and build on each other, their amplitudes add up. This is the definition of constructive interference. Destructive interference is when waves cancel each other out. Reflection is when a wave bounces back from a boundary, and absorption is when a wave's energy is taken in by a medium.

Answer:

constructive interference