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]: 7, 8, ['9589', 'N', 'w', '429', '5545', '5047', '4133', 'p', 'a', '3793']
[EX A]: p3314

[EX Q]: 2, 3, ['c', 'G', '8603', 'd']
[EX A]:
3068G