PLEASE ANSWER 4a and 4b and show work

4. For a particular computer, the CPI for certain types of instructions is as follows: - - - ALU operations, 1 cycle, make up 20% of dynamic (run-time) instruction count Load/store operations, 5 cycles, 40% of dynamic instruction count Control flow, 3 cycles, 20% of dynamic instruction count All other, 2 cycles, 20% of dynamic instruction count a. What is the average CPI? b. Suppose there is an optimization in which the CPI of load/store is reduced to 2, but cycle time is lengthened by 10%. What is the speedup due to this optimization