Consider two different implementations of the same instruction set architecture. There are thre classes of instructions, A, B, and C. The clock rate and CPI of each implementation are given in the following table. Given a program generates code with 4 billion Class A instractions, I billion Class B instructions, and 2 billion Class instructions Processor PO P2 Clock Rate 2 GHz 4 GHz CPI Class A 1 2 CPI Class B 2 4 CPI Class C 3 2 What is the execution time of processor P12 2