In the U.S., the customary measure of a car's fuel efficiency is the car's gasoline usage measured in miles per gallon (MPG), but some advocate the use of "inverted" measures like gallons per hundred miles

For this question I completed parts a, b, and part of c could you check my work and help me with the other parts

(1) . (a) Write down a function f(x) that gives the number of gallons it would take a car that gets x MPG to go 100 miles.

(b) Use the definition of the derivative to find f 0 (x). (1)

(c) Find the average rate of change of f(x) when x increases from 15 MPG to 20 MPG, as well as the average rate of change of f(x) when x increases from 45 to 50 MPG. (Include units with your answers.)

(d) Find the instantaneous rate of change of f(x) when x is 15 MPG and when x is 45 MPG. (Include units with your answers.)

(e) Some analysts contend that it is more important to improve low-efficiency (rather than highefficiency) vehicles; that is, they say there is a greater impact from replacing an old SUV with a more efficient SUV than there is from replacing an old subcompact with a Prius. Explain how your answer to either (c) or (d) might be used either for or against this argument.