Barnacles and whales have a commensalistic relationship in which barnacles benefit. what would most likely happen to the whale population if the barnacle population decreased?

There will be no impact on the whale’s population.  

Explanation:

Barnacles and whales have a commensalistic relationship which is a kind of symbiotic relationship. In this kind of symbiotic relationship, two species live in association with each other where one species gets the benefit of this relationship while the other is neither harmed nor benefited.  

In the case of barnacles and whales, barnacles are the species which gets benefited from this relationship as they attach to the belly or back of a whale’s body and then feed on the microorganisms while whales are neither befitted nor harmed by this association. Thus, if barnacles population decreases there would be no impact on the whale’s population.  

sea breeze

explanation:

cool air is going towards land allowing for the land to be cooler, the hotter air gets pushed away from the land.