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.

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

7, 8, ['8275', 'o', 'f', '6403', '7399', 'M', 'E', '7879', 'e', 'L', 'F', '2019']
9787E

6, 7, ['315', '7787', 'J', '9533', 'r', 'k', '1091', 'Z', 'P', 'k', 'L']

1901k