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: 8, 12, ['C', 'w', 'Q', '8125', '4579', '8495', '363', 'a', 'C', 'T', '7905', '2631']

SOLUTION: 13625097TCa

PROBLEM: 19, 20, ['w', '4131', 'C', '719', '2961', 'Q', '4167', '1001', 'p', '965', '1153', '6881', '3361', 'H', 'f', 'V', '9393', 'x', '6091', 'B', '6757', 'U', '2619', '5649', '6447', 'D']

SOLUTION: B1906

PROBLEM: 3, 5, ['7677', '7235', 'F', 'G', '6691', '7289', '5765', '1057', '6517', '289', '5139', 'N', 'k', 'S']

SOLUTION:
1966GF