Chapter 6.1, Problem 85E

Oil production. Using production and geological data, the management of an oil company estimates that oil will be pumped from a producing field at a rate given by

     $R\left(t\right)=\frac{100}{t+100}+100\le t\le 15$

Where R(t) is the rate of production (in thousands of barrels per year) t years after pumping begins. Find the area between the graph of R and the t axis over the interval [5, 10] and interpret the results.