Graph N and N' on the same coordinate system. Choose the correct answer below. O A. 110000 Ay ○ c. B. Ay 110000 110000 N Q 16 N 50 E N' 16 50 16 50 O D. 110000 G N' 0+ 16 50 Q A company estimates that it will sell N(X) units of a product after spending $x thousand on advertising, as given by N(x) = -0.25x4 + 22x³-472.5x² + 76,000, where 21 ≤x≤45. When is the rate of change of sales increasing and when is it decreasing? What is the point of diminishing returns and the maximum rate of change of sales? Graph N and N' on the same coordinate system. The rate of change of sales is increasing on (Type your answer in interval notation.) The rate of change of sales is decreasing on (Type your answer in interval notation.) The point of diminishing returns is thousand dollars. sales per thousand dollars. The maximum rate of change of sales is (Round to the nearest whole number as needed.)