Final answer:
A producer can increase their surplus by creating trade barriers to raise prices and decrease competition, but this will decrease consumer surplus and possibly market efficiency.
Step-by-step explanation:
As a consumer or producer in a market at equilibrium, increasing your surplus means you are looking to benefit more from the trade than the current balance. For a producer, increasing surplus could be achieved through creating barriers to trade such as tariffs or import quotas, which reduce competition and allow domestic prices to rise. As the price increases to PNoTrade, the quantity supplied domestically increases, raising the producer surplus.
Step 7 in the provided instructions suggests comparing the areas of two triangles to visualize the gain in producer surplus. However, this action comes at the expense of the consumer surplus, which diminishes as consumers are faced with higher prices and a lower quantity offered. While the producer may gain, the overall efficiency of the market could decrease, implying that the economy is not getting as much benefit as possible from its scarce resources.