Exercise 18-2 b-d Cullumber Enterprises is considering manufacturing a new product. It projects the cost of direct materials and rent for a range of output as shown below. Output Rent Direct in Units Expense Materials 1,000 $5,290 $4,232 2,000 5,290 7,200 3,000 8,464 7,200 4,000 8,464 9,600 5,000 8,464 12,000 6,000 8,464 14,400 7,000 8,464 16,800 8,000 8,464 19,200 9,000 10,580 30,999 10,000 10,580 37,030 11,000 10,580 46,552 (b) Determine the relevant range of activity for this product. The relevant range of activity for this product units Calculate the variable costs per unit within the relevant range. (Round answer to 2 decimal places e.g. 2.25.) Variable costs per unit per unit $ (d) Indicate the fixed cost within the relevant range. Fixed cost $