Consider a processor with a delayed branch that has three delay slots. Three compilers compiler A, compiler B and

Consider a processor with a delayed branch that has three delay slots. Three compilers compiler A, compiler B and
compiler C, could run on this processor. Compiler A can fill the first delay slot 60% of the time and the second
delay slot 40% of the time and the third delay slot 20% of the time (filling delay slot is independent). Compiler B
can fully fill all the three delay slots. Compiler C leaves all the slots empty. Assuming that branches account for
20% of all instructions and arithmetic/logic operations for the remaining 80% of the instructions for any program,
what is the improvement of CPI with compiler B compared to CPI with compiler A and compared to CPI with
compiler C? Assume that CPI of arithmetic/logic operations is 1.