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, 9, ['s', '3175', '1431', 'a', 'u', '7265', 'N', 'H', '1217', 'x', 'u', 'a', 'c', 'n', 'b', 'J', 'B', '6907', 'D', '6691', 'N', '7959', 'm']
[EX A]: 7121HN

[EX Q]: 1, 4, ['6193', '5871', '9871', '4821']
[EX A]: 1284178917853916

[EX Q]: 3, 4, ['S', 'J', 'p', 'J', '125', 'i', 'e', 'Q', 'Y', 'Z', '2973']
[EX A]:
Jp