please answer this question!

Consider the function f() = x -101 tan a Find the critical number(s) of f in the interval [0, 21), Find the values of ac in the interval (0, 21) at which the function attains its absolute maximum and absolute minimum values. Answer: The critical number(s) of f in the interval [0, 21] is a = The absolute maximum of the function f occurs at a = The absolute mimnimum of the function f occurs at a: = d si