The fouling on the heat exchanger surfaces causes additional thermal resistance, thus decreases the heat transfer rate. a)- true b)-false

True

Explanation:

First, it must be known that heat transfer is equal to the temperature difference divided in the thermal resistance, so the fouling that is a layer of dirt that accumulates on the surface of the heat exchanger over time this layer ends up becoming an additional thermal resistance, increasing the total thermal resistance, giving a drop in the rate which the heat is transferred, so in this case the statement would be true.