Now, consider two people in the market for tilapia, Rowan and Cheryl. The marginal benefit curves for both individuals are shown in the accompanying graph.

If the market price is $21 per kilogram of tilapia, how many kilograms would Rowan purchase? How many kilograms would Cheryl purchase? How many total kilograms will they collectively purchase? Is this allocation the most allocatively efficient way to distribute this quantity of tilapia?