a) What is the role of the base cases in a recursive Java method? b) Exponentiation can be implemented efficiently using the following equations. x^0 = 1 x^2n = (x^2)^n x^2n + 1 = x^2n * x Write the recursive method exp that calculates x^n using this algorithm.//returns x raised to the power n public static double exp (double x, int n) c) Show the sequence of method calls that your definition generates for the invocation exp (3, 6)