(a) Estimate the area under the graph of the function f (x) = 1 from r = 0 to x = 5 using a Riemann sum with n = 10 subintervals and right endpoints. Round your answer to four decimal places. area = Number (b) Estimate the area under the graph of the function f (x) = 1 from r = 0 to x = 5 using a Riemann sum with n = 10 subintervals and left endpoints. Round your answer to four decimal places. area = Number