can you please help me out, i have been stuck on this question and can not figure it out, and guidance would be greatly appreciated. Thank you.

Brian wants to sell t-shirts for the Crosstown Showdown. He purchases the shirts for $7 and plans to sell them to UC basketball fans for $10. He has to pay a service fee of $500 to be able to sell them on campus. Assume there is no value for any t-shirts that are unsold before the start of the game. The payoff, if he orders 1500 and demand is 1350, is