Question

fill in the blank: __________ is a layer in the ocean where density changes rapidly with depth. pycnocline abyssal plain halocline thermocline

Explanation:

The pycnocline is the ocean layer where density changes rapidly with depth. An abyssal plain is a flat - area on the ocean floor. A halocline is where salinity changes rapidly with depth and a thermocline is where temperature changes rapidly with depth.

Answer:

Pycnocline