Computer Architecture.

5. A system that uses a Translation Look-aside Buffer (TLB) has three possible scenarios when handling a memory reference: 1) there can be a hit in the TLB 2) there can be a TLB miss but the page is mapped or 3) there can be a TLB miss and the page is not mapped. A) Which of the three causes a page fault? Explain. B) Which of these causes a disk access. C) Is the disk access in part B handled by the operating system or by hardware? Explain