Perform a first derivative test on the function f(x)=4x5-5x4-40x33; [-3,4.a. Locate the critical points of the given function.b. Use the First Derivative Test to locate the local maximum and minimum values.c. Identify the absolute maximum and minimum values of the function on the given interval (when they exist).a. Locate the critical points of f . Select the correct choice below and, if necessary, fill in the answer box to complete your choice.A. The critical point(s) is(are) at x=(Use a comma to separate answers as needed. Type an integer or a simplified fraction.)B. The function does not have a critical value.