The many identical residents of Whoville love drinking Zlurp. Each resident has the following willingness to pay for the tasty refreshment:
Quantity Willingness to Pay (Dollars)
First bottle 10
Second bottle 8
Third bottle 6
Fourth bottle 4
Fifth bottle 2
Further bottles 0
The cost of producing a bottle of Zlurp is $3.50, and the competitive suppliers sell it at this price. (The supply curve is horizontal.)
Each Whovillian will consumebottles and receive a consumer surplus of $. Producing Zlurp creates pollution. Each bottle has an external cost of $1. Taking this additional cost into account, total surplus per person in the allocation you previously determined decreases to $.