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Suppose a computer using set associative cache has 2²¹ words of main memory and a cache of 64 blocks, where each cache block contains 4 words.

a.    If this cache is 2-way set associative, what is the format of a memory address as seen by the cache, that is, what are the sizes of the tag, set, and word fields?  Tag 14, set 32, word 2

b.    If this cache is 4-way set associative, what is the format of a memory address as seen by the cache? Tag 15, set 16, word 2