Question: Given \(f\left( x \right)=\frac{5\ln x}{x}\)

(a) Use 4 left rectangles to approximate the area bounded by \(f\left( x \right)\) and the x-axis between x = 26 and x = 49.

(b) Now suppose that the function \(f\left( x \right)\) gives the rate of change of the price of hardcover novel \(f\left( x \right)=\frac{5\ln x}{x}\) dollars per year, x years after 1950. What are the units of the rectangle heights?

(c) What are the units of the rectangle widths?

(d) What are the units of the rectangle areas?