In this task, you are given inputs 'i', 'j', and A, where 'i' and 'j' are integers and A is a list. A list is shown by two brackets and comma-separated numbers and characters inside, like ['1', '12', 'l']. You need to concatenate all elements of A from the ith element to the jth element, and then reverse the resulting string. 'i' and 'j' will be non-negative, and will always have a value less than the length of A. 'i' will always be less than 'j'. Perform the operations in order, i.e., do not reverse first and then concatenate.
21, 28, ['U', 'c', '5275', 'u', '9365', '2819', '8295', 'S', 'n', 'X', 'o', '8139', 'G', '7499', '9127', 'O', 'u', 'G', '535', '4857', 'K', 'W', '6725', 'q', '115', '4781', '4709', 'C', 'M']