4. Amdahl's law F: represents the fraction of a program's running time due to unparallelizable computation. The rest part. (1-1), of the program enjoys the prefect speed up of p when run on p processors. The speed up s: 1 S = f+(1-1)/P s min(p.5 A Processor chip is used for applications, in which: 30% time floatine point addition 25% time-floating point multiplication 10% timo floating point division A new model has 3 possible enhancements, cost roughly the same, which one should be chosen? A redesign the floating-point adder to make it twice as fast Bredeshen the floating point multiplier to make it 3 times as fast C. redesign the floating point divider to make it 10 times as fast