Given a scenario where there are four frames. The following table shows the loading time of a page into each page frame, the time of last access to the page, and the Referenced (R) and Modified (M) bits for each page frame (the times are in clock ticks from the process start at time 0). Table 1: Virtual Page Information Virtual Page Time Number Loaded Referenced Time R M bit bit 3 136 245 1 1 1 98 214 1 0 0 125 240 1 0 2 76 255 1 1 a. A page fault to virtual page 4 has occurred at time 256. Which page should be replaced for each of the following memory management policies? i FIFO ii. LRU b. Consider the following virtual page reference string, that includes the initial placement of virtual page in memory (as in Table 1) just before the page fault: 1,0,3,2, 4, 5,0,1,3,4, 2, 5, 4, 1 How many page faults would occur if Optimal policy were used? Show clearly when each page fault would occur