Consider a computer system with ten physical page frames. The system is provided with an access sequence (a1, a2 ,..., a20, a1, a2,..., a20), where each ai is a distinct virtual page number. The difference in the number of page faults between the last-in-first-out page replacement policy and the optimal page replacement policy is _________.

Consider a computer system with ten physical page frames. The system i

1.	Consider a computer system with ten physical page frames. The system is provided with an access sequence (a1, a2 ,..., a20, a1, a2,..., a20), where each ai is a distinct virtual page number. The difference in the number of page faults between the last-in-first-out page replacement policy and the optimal page replacement policy is _________.
A.	1
B.	2
C.	3
D.	4
Answer» B. 2

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