Answer:
b) $0, since he was just going to throw out the board
Explanation:
Producer surplus would have applied if the old surfboard that he no longer needs was produced by him.
Producer surplus measures the benefit to sellers of participating in a market. It is measured as the amount a seller is paid minus the cost of production. For an individual sale, producer surplus is measured as the difference between the market price and the cost of production, as shown on the supply curve.
There is a difference between profit and Producer Surplus which is the fixed cost of production.
In conclusion Steve benefited $10 but that cannot be called a producer surplus.