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.

3, 20, ['x', 'S', 's', 'a', '5077', 'D', '3979', 'I', '3129', 'R', '8517', 'r', 'l', 'K', 'N', '9701', '227', 'n', '9385', 'U']
U5839n7221079NKlr7158R9213I9793D7705as

2, 9, ['7175', '1487', '4759', '8719', 'f', '9899', '1987', 'h', 'o', '5495', '3665', 'k', 'j', 'C', 'H', 'V', '9443', '1203', 'j', 'p']
oh78919989f917895747841

8, 15, ['6967', 'D', '9241', '4927', '8691', '9853', '3855', 'k', 'B', 'F', 'U', 'U', 'r', '1265', 'b', 'c', 'p', '7597', '929', 'y', 'C', 'K']

b5621rUUFBk