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.

[EX Q]: 7, 18, ['4879', '857', 'X', '8629', 'K', 'l', 'U', '5611', '5989', '4439', '4897', 'D', 'p', '8109', 'F', 'a', '4665', 'Q']
[EX A]: Q5664aF9018pD7984934498951165U

[EX Q]: 1, 3, ['8015', 'y', 'r', '8077', 'U']
[EX A]: ry5108

[EX Q]: 13, 16, ['1863', 'c', 'c', 'h', 'w', 'W', '7913', '2285', '7859', '9263', 'V', '6229', 'e', 'A', '5079', '9459', 'H', '6649', '8209']
[EX A]:
95499705Ae