Yang Manufacturing makes a product called Yin. The relevant range of operations is between 2 500 units and 10 000 units of Yin per month. Per unit costs at two activity levels are as follows: 5 000 units at $17.00 per unit; 7 500 units at $13.00 per unit. Determine the cost formula that expresses the behaviour of Yang's total costs:

Group of answer choices

Y$60 000 + $5X

Y$20 000 + $13X

Y$45 000 + $4X

Y$40 000 + $9X