Consider a computer system where the overhead required for reading a word from the page table is 1.25ms. A TLB lookup of a word requires 250 ns.

1.     What would be the mean access time for reading a word from a virtual address if the TLB hit rate was 100%?

2.     What would be the mean access time for reading a word from a virtual address if the TLB miss rate was 90%? Show your work for partial credit.

3.     What hit rate is needed to reduce the mean access time for reading a word from a virtual address to 500 ns? Show your work for partial credit.