3. Consider two different implementations of the same instruction set architecture. The instructions can be divided into four classes according to their CPI (A, B, C, and D). P1 with a clock rate of 2.5 GHz and CPIs of 1, 2, 3, and 3, and P2 with a clock rate of 3 GHz and CPIs of 2, 2, 2, and 2. Given a program with 1.0E6 (106) instructions divided into classes as follows: 10% class A, 20% class B, 50 % class C and 2000 class D, which implementation is faster? a) What is the global CPI for each implementation? b) Find the clock cycles required in both cases