Pomona operates a landfill and accounts for it using enterprise fund. The closure costs are estimated to be $60 million. If max capacity of this landfill is 10 million tons of waste and that waste will be accepted for 6 years. During 2020, 6 million tons of waste was accepted. The charge costs for 2020 would be: a. $ 4 million. b. $ 7 million. c. $ 6.67 million. d. $ 36 million.