Four Stores Have a Problem with Theft and Security Is

Multiple Choice

Four stores have a problem with theft and security is a public good.Let S stand for the number of person-hours of security patrols per week.The marginal benefit of security patrols to each of the stores is given by the formula MB = 200/(1 + S) .Patrols cost $25 per hour.If each store provided security independently,how much would each store purchase?

A) 15 person-hours of patrols per week
B) 7 person-hours of patrols per week
C) 8 person-hours of patrols per week
D) 16 person-hours of patrols per week