Problem I: (6 Points total) Consider the following page reference string, S: 4, 1, 5, 4, 1, 2, 3, 6, 1, 2, 1, 5, 4, 2, 1, 2, 5, 7, 2, 5 Assume there are 3 page frames. a. Using the above reference string verify the statement on page 412 of the textbook that the number of faults on a reference string for the LRU algorithm is the same as the number of faults on the reverse of the string. b. Using the above reference string verify the statement on page 412 of the textbook that the number of faults on a reference string for the OPT algorithm is the same as the number of faults on the reverse of the string.