3.) [25 points] Assume a system contains two levels of caches and main memory, assume all data can be found in main memory. The hit rate and hit times for each are: Hit rate | 50% L1 L2 Main Memory Hit times (cycles) 2 10 200 100% a. [5 points] What fraction of accesses are serviced from main memory? b. [10 points] What is the miss rate and miss time for L1? c. [10 points] What is the average accessing time? Compare with the average accessing time without L2 (only L1 and main memory)