A ship owner expects his new ore carrier to move 230000+50000*(-1)^{last digit of student number} tons of cargo per year on a given trade route.

The ship will cost $4000000+$500000*(-1)^{last digit of student number} to built will last 25 years. Its average annual operating cost will be $900000+$100000*(-1)^{last digit of student number}.

The ship owner profits tax rate is 35 percent. What revenue per ton must he charge if he is to earn 20 percent interest on his investment after taxes?

Last dgt of student number = 6