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2) Suppose three interrupts, 11,12 , and 13 , occur at times t=10,t=20, and t=30 as shown in the table below. Also in the table are the priorities of each interrupt (higher number, higher priority), and the time required for the handler to process each interrupt. a) When does each of the three interrupts finish if the OS disables interrupts while an interrupt is being processed? I1 finishes at t= 12 finishes at t= 13 finishes at t= b) When does each of the three interrupts finish if the OS processes multiple interrupts using a priority scheme? I1 finishes at t= 12 finishes at t= 13 finishes at t= 3) Consider the multi-level memory profile below: Level 1: 1000 bytes 0.5t access time Level 2: 1000KB1.0t access time Below what hit ratio is this multi-level scheme doing more harm than good? Put another way, at what hit ratio would we be better off with just level 2 memory? Refer to the hit ratio example in the slides to get started