TASK DEFINITION: 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.
PROBLEM: 7, 8, ['k', '59', 'Q', 'b', 'N', '5153', 'm', 's', '1703', 'i', 'E', 'x', '4727', '9723', '9305', '8843', '5295', '4281', '555']

SOLUTION: sm

PROBLEM: 8, 9, ['s', 'X', '6737', 'M', 'm', 'N', 'a', 'Q', 't']

SOLUTION: tQ

PROBLEM: 1, 10, ['x', '8939', '3827', '8077', '9161', '857', '6363', '5133', '921', 't']

SOLUTION:
t129331536367581619770872839398x