To calculate the left Riemann sum for the function f(a) = a3 - 8 on the interval [1, 3] with n = 8 subintervals, what is Ax? Write as a decimal. Question 3 1 pts Select all of the statements which are true about the definite integral. The value of the definite integral can be 0. O A function with a jump discontinuity is not integrable. The definite integral from a to b is equal to the average value of the function on the interval [a, b]. The value of the definite integral can be negative. O The definite integral represents the area under the curve, and thus is always positive