(a) Use the Midpoint Rule with n = 4 to approximate the integral. (Use decimal notation. Give your answer to three decimal places.) 2 1 3.91] / ex ,4 dx x 0 Incorrect (b) Estimate the error in using the approximation. (Use decimal notation. Give your answer to four decimal places.) 0.0104 error 3 Incorrect (c) Determine the number of subintervals needed to guarantee that an approximation has an error less than or equal to 0.0001. 41 Incorrect