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.

[Q]: 3, 21, ['V', '3661', '3743', 'Y', '3179', 'b', '7097', '3031', '5859', '4095', 'D', 'J', '2337', '4259', '2539', 'I', '9659', 'U', 'G', 'Q', '3145', '177', '9839', 'f']
[A]: 5413QGU9569I935295247332JD5904958513037907b9713Y3473


[Q]: 13, 15, ['L', 'A', '2959', 'g', '7157', '9131', 'o', 'D', 'q', 'd', 'A', '4249', 'K', 'U', '4805', 'h', '7981']
[A]: 5084UK


[Q]: 9, 15, ['2585', 'G', 'n', 'G', 'p', '2211', '7609', 'C', '1991', 'G', '697', 'n', 'U', 'L', 'l', '3747', '1047', '147', 'f', '5257', '831', '7867', 'o', '7707', '8373', '1911', 'T', '4855', 'v']
[A]:
lLUn796G1991