Hey this was a question from an old test, can you guys please help me with this one?

3. (20 points) cache memories (10 points) Assume a cache hit costs 1 ns of delay and a cache miss costs 100 ns of delay. 2 poins What cache hit rate is requied to achieve an average 2 points What cache hit rate is required to achieve an average 2 points What cache hit rate is required to to achieve a average 4 points What cache hit rate is required to achieve a average of access time of 1 ns ine o hal che ht rate is required to to of 10ns 50 ns (10 points) Assume you have a set associative cache memory (5 points) When we divided up the virtual page of an address into two parts, why did we choose the middle bits to select the set (5 points) What factors limit the size of a set (number of entries)