4. Consider a paging system with the page table stored in memory. i) If a memory reference takes 150ns, how long does a paged memory reference take? (Note: in this case there are no Translation Look-Aside buffers i.e. any TLBs). ii) If we add TLBs, and we have a hit ratio of 80%, what is the effective memory access time? Assume that finding a page table entry in the TLBs takes 20ns if the entry is there