A local business owner is considering adding another employee to his staff in an effort to increase the number of hours that the store is open per day. If the employee will cost the owner $4,000 per month and the store takes in $50/hour in revenue with variable costs of $15/hour, how many hours must the new employee work for the owner to break even?

a. 61.5 b. 160.0 c. 266.7 d. 114.3 e. 80.0