What is the internal rate of return? Pick the closest interest rate from the present value of annuity tables.

Big Al gives his worker's a one hour lunch and two fifteen minute breaks each day. He believes that a cold soda machine would be appreciated by his workers, and an appreciated worker is a good worker. He has priced a machine at a national member only warehouse for $2,250. The machine should be usable for 6 years, after which it would be inefficient, obsolete and would have to be disposed of at the dump. Big Al believes that 7 cans a day will be purchased. The plant is open five days a week, 50 weeks per year. A case of soda ( 24 cans) costs $6.48 and Big Al believes that a price of $.70 per can would win him good will