Use equal width rectangles to estimate the area under the graph of f(x)=2+2^(x/8) from x=0 to x=8. Round your answers to three decimal places. a) Estimate the area using four rectangles that take the sample points from the left endpoints. b) Estimate the area using four rectangles that take the sample points from the right endpoints. c) Estimate the area using eight rectangles that take the sample points from the left endpoints. d) Estimate the area using eight rectangles that take the sample points from the right endpoints.