Problem 2 (14 pts) a) Assume a program requires the execution of 100 x 106 FP instructions, 220 x 106 INT instructions, 160 x 106 L/S instructions and 32 x 106 Branch instructions. The CPI for each type of instruction is 2, 2, 8, and 4, respectively. Assume that the processor has a 4 GHz clock rate. By how much must the CPI of L/S instructions be improved if the program is to run two times faster? b) What percentage of the code of a program has to be parallelizable and what percentage can be run sequentially on a 128 processors system to achieve a speedup of 20