The wrench factory is producing 1000 wrenches with an average total cost of 4 and a marginal cost of 5. Which of the following is true?
1) The total cost of producing 1000 wrenches is 4000
2) The total cost of producing 1000 wrenches is 5000
3) The total cost of producing 1000 wrenches is 6000
4) The total cost of producing 1000 wrenches is 7000