Use an appropriate test method to determine whether each of the following series is convergent of divergent. NAME the test method that you use in your answer. STATE the condition(s) why this test method applies, but you don't need to PROVE the conditions are true for this question. (For example, you may say "an is decreasing", but you don't need to PROVE that an is indeed decreasing.) (a) 255 2 \"(1.11 )13;'2 n 1 (b) 251 {5+1