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]: 8, 21, ['9847', '3163', 'L', 'E', 's', 'I', 'H', 'e', 'l', '8875', '547', 'F', '4221', '5105', '5409', 'M', '6617', 'Z', 'g', '9257', 'l', 'q', 'p', 'Q', '6755', '265', '9845']
[EX A]: l7529gZ7166M904550151224F7455788le

[EX Q]: 3, 6, ['6843', '7805', 'h', '9097', 'O', 'u']
[EX A]: uO7909h

[EX Q]: 9, 12, ['7053', 'n', 'D', '2249', 'P', '1407', 'v', 'P', 'S', 'o', 'U', '5695']
[EX A]:
5965UoS