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.
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Question: 1, 2, ['4857', '9647']

Answer: 74697584


Question: 3, 6, ['643', 'X', 'F', '7453', '8495', '7943']

Answer: 349759483547F


Question: 4, 4, ['163', 'Q', '1269', 'U', 'I', 'B', 'L', 't', '5741', '1055', '2045', '3871']

Answer:
U