For the series below, find the series' radius and interval of convergence. For what values of x does the series converge (b) absolutely, (c) conditionally?
∑ (x+3)^2/4^n, n=0 to ∞
(a) The radius of convergence is (Type an integer or a simplified fraction). Determine the interval of convergence. Select the correct choice below and, if necessary, fill in the answer box to complete your choice.
A. The interval of convergence is 7 < x < (Type a compound inequality. Simplify your answer. Use integers or fractions for any numbers in the expression.)
B. The series converges only at x= (Type an integer or a simplified fraction.)
C. The series converges for all values of x
(b) For what values of x does the series converge absolutely? Select the correct choice below and, if necessary, fill in the answer box to complete your choice