Computer Architecture question. Also add comments to help me better understand and put units(because I'm confused with the corresponding units).

Consider two different implementations of the same instruction set architecture. The instructions can be divided into four classes according to their CPI (class A, B, C, and D). P1 has a clock rate of 2.5 GHz and P2 of 3 GHz. For a program with (dynamic) instruction count of 1012 instructions divided into classes as 10% class A, 20% class B, 50% class C, and 20% class D 3. Class CPI on P1 (a2.5 GHz) CPI on P2 (a3GHz)Instruction 2 2 4. Frequency 10% 20% 50% 20% 4. (a) What is the average CPI for each of the implementations? (b) What is the execution time of the program for each of implementations