Suppose Troutsville (population of 4) wants to put on a firework display. Leslie would get $40 worth of benefit, Mark would get $30 worth of benefit, Maggie would get $20 worth, and Erika would get $10 worth. What is the socially efficient amount to spend on the display?
a. $25, the average of their benefits
b. $10, the minimum of their benefits
c. $40, the max of their benefits
d. impossible to tell
e. $100, the sum of their benefits