A computer spends 30 percent of its time accessing memory, 20 percent performing multiplications, and 50 percent executing other instructions. As a computer architect, you have to choose between improving either the memory, multiplication hardware, or execution of other instructions. There is only space on the chip for one improvement, and each of the improvements will improve its associated part of the computation by a factor of 2. a. Without performing any calculations, which improvement would you expect to give the largest performance increase, and why? b. What would be the overall speedup for each of the three changes?