A certain manufacturer uses the function \(C(x)=0.04x^2-8.5x+25,000\) to calculate the cost, in dollars, of producing \(x\) thousand units of its product. The table above gives values of this cost function for values of \(x\) between \(0\) and \(50\) in increments of \(10.\) For which of the following intervals is the average rate of decrease in cost less than the average rate of decrease in cost for each of the other intervals?
A. From \(x = 0\) to \(x = 10\)
B. From \(x = 10\) to \(x = 20\)
C. From \(x = 20\) to \(x = 30\)
D. From \(x = 30\) to \(x = 40\)
E. From \(x = 40\) to \(x = 50\)
Answer:
E
Source: Official Guide
