1. [30 points] You have been asked to evaluate server performance, so you decide to run a benchmark program that finds out memory operations currently take 45% of execution time. Your team is evaluating two server upgrade options that can help improve performance: Option 1: the new server architecture uses a memory cache which speeds up 75% of memory operations by a factor of 5. Option 2: same as Option 1 along with an additional level (L2) cache which speeds up 1/2 the remaining 25% of memory operations by a factor of 3.
   1. Calculate the overall speedup for Option 1?
   2. What is the overall speedup for Option 2?
   3. What is the upper bound on overall speed-up from any additional optimizations that could be done for the L2 cache described in Option 2?