Given the revenue and cost functions R(x) = 28x- 0.5x2 and C(x) = 4x + 15, where x is the daily production, nd the rate of change of revenue dx with respect to time when x = 15 units and m =4 units per day. {:2 A. $92.00/day {:3 B. $36.00/day {:2 c. $52.00/day {:3 D. $81.00/day A company knows that the unit cost C and the unit revenue R from the production and sale of x units are related by C = 300,000 + 7926. Find the rate of change of unit revenue when the unit cost is changing by $11/unit and the unit revenue is $4,000. Round to the nearest cent. . . . O A. $602.55/unit O B. $220.00/unit O C. $412.50/unit O D. $792.60/unit