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: 13, 18, ['1931', '2101', 'U', '3395', '7549', '5187', '4669', '9151', '6971', '5793', '2173', '2279', 'h', 'w', 't', '4769', '6581', 'D']

Answer: D18569674twh


Question: 9, 21, ['D', 'j', 'T', '91', 'W', '9709', 'H', '1023', '4595', '1241', '917', '383', '7739', 'G', 'I', 'b', '8401', '7941', 'j', '2713', 'K', '2443', 'E', 'B', '1515', '5141', '1221', '993']

Answer: K3172j14971048bIG937738371914215954


Question: 21, 21, ['e', '8675', '6937', 'o', '2985', '5179', '323', 'S', 'H', '2985', 'H', '6521', '4311', 'H', 'I', '2179', '4653', '7787', 'P', '429', '9883', '3897', '6837', 'y', 'Q', 'L']

Answer:
3889