Use the Master Method to find out the approximate solution for the following complexity recurrence relations. Be sure to identify the values of a, b, and k in your answer.
a. T(n) = 5 * T(n/4) + n -3
b. T(n) = 9*T(n/3) + n2 + 4
c. T(n) = 6 *T(n/2) + n2 -2