Answer:
a. $1,790,000.
Step-by-step explanation:
operating profit:

Total fixed cost
276,000 + 172,000 = 448,000
Total variable cost
72 + 61 = 133
Selling price: 190
We solve for Q
(190-133)xQ- 488,000 = 89,000
Q = (89,000 + 488,000) / 57
Q = 9.421,05
This will be the amount of units. we multiply by the selling price and get the volume of sales to achieve 89,000 profit:
9.421,05 x 190 = 1,790,000