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]: 6, 8, ['u', 'y', '5599', 'i', 'Z', 'F', '8907', 'A', 'l', '8821', 'B', 'G', 'd']
[EX A]: A7098F

[EX Q]: 17, 21, ['5503', '2979', '6307', '633', 'n', '9339', '5829', '5291', '8967', 'i', '9063', '975', 'G', '9187', '3227', 'A', '3487', '8187', 'H', '6097', 'H']
[EX A]: H7906H78187843

[EX Q]: 6, 8, ['5923', 'k', '2183', '1725', '7419', '2199', 'g', 'm', 'a', '6953']
[EX A]:
mg9912