A continuously decreasing function that is concave down on the interval [0, 4] is represented by the table. X 1.2 2.7 3.5 4 f(x) 0 -1.44 -7.29 -12.25 -16 Part A: Find the right Riemann sum estimate of [" f(x)dx, using the subintervals given in the table. (10 points) Part B: Find the left Riemann sum estimate of (" f(x)ax, using the subintervals given in the table. (10 points) Part C: Find the trapezoidal estimate of ["f(x)dx, using the subintervals given in the table. (15 points) Part D: Determine whether the right Riemann sum estimate is an overestimate or an underestimate, based on the properties of the function. (5 points)