5. A series 2 a], is called absolutely convergent if the series 2 lakl converges. Decide Whether or not each of the following series is absolutely convergent. Explain your reasoning in each. (Notice that, When you decide Whether 2a,, is absolutely convergent, you're not looking at Zak at all; instead, you're looking at the series 2 lakl, Whose terms are all non-negative). You do not need to use asymptotic comparison test (limit comparison test) here. 00 sink (a) 2 2k k=1 (b) gWl