2. Let's assume that there are three processors, Pa, Pb, and Pc, that support different ISA3. Note, you can assume that 1-way superscalar, no hyper-threading, and no pipeline for all processors. Pa: 4.2 GHz clock rate, CPI: 2.1, ISA: A Pb: 2.5 GHz clock rate, CPI: 1.2, ISA: B Pc: 3.5 GHz clock rate, CPI: 1.7, ISA: C 2.1. (15 points) Assume that you write a program using an assembly language for Pa. Can the program run on Pb and Pc? Explain your answer. hello.c and goodbye.java. 2.2. (15 points) Assume that you write two programs, Explain how these programs can run on these CPUs. 2.3. (20 points) Find a CPU that executes the most number of instructions per second