You are going to enhance a computer, and there are two possible improvements: either make multiply instructions run four times faster than before, or make memory access instructions run two times faster than before. The computer is used for a program that takes 100 seconds to execute. Of this time, 24% is used for multiplication, 50% for memory access instructions, and 26% for other tasks.

(a) What will the speedup (ratio of old to new execution time) be if only multiplication is improved?

(b) What will the speedup be if only memory access is improved? (c) What will the speedup be if both improvements are made?

(2 marks) Suppose that a SPEC benchmark suite contains 4 benchmarks, with running times on a system A of 5, 8, 2, and 50 seconds, respectively, and running times on a system B of 4, 11, 6, and 30 seconds, respectively. Which system would have a better (i.e. larger) SPEC rating, and by what factor?