4.22 [5] <§4.3> 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. You repeatedly run a program that takes 100 seconds to execute. Of this

time, 20% is used for multiplication, 50% for memory access instructions, and

30% for other tasks. What will the speedup be if you improve only multiplication?

What will the speedup be if you improve only memory access? What will

the speedup be if both improvements are made?