6. Consider a paging system with the page table stored in memory (2 pts) a) If a memory reference takes 200 nanoseconds, how long does a paged memory reference take? b) If we add TLBs, and 75 percent of all page-table references are found in the TLBs, what is the effective memory reference time (or expected memory reference time)? (Assume that finding a page-table entry in the TLBs takes zero time if the entry is there.)