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]: 1, 2, ['3909', '5863', '707']
[EX A]: 36859093

[EX Q]: 19, 20, ['w', '4131', 'C', '719', '2961', 'Q', '4167', '1001', 'p', '965', '1153', '6881', '3361', 'H', 'f', 'V', '9393', 'x', '6091', 'B', '6757', 'U', '2619', '5649', '6447', 'D']
[EX A]: B1906

[EX Q]: 5, 16, ['x', 'S', '7959', '399', '2487', 'y', 'q', '745', '1985', '1553', '3571', '6815', 'c', '8843', '2033', '1489', 'D', '4769', '7047', 'Z']
[EX A]:
984133023488c5186175335515891547qy7842