Q$.2[50]$ Cache organization is often influenced by the desire to reduce the cache's power consumption. For that purpose, we assume that the cache is physically distributed into a data array $($holding the data$),$ tag array $($holding the tags$),$ and replacement array $($holding information needed by replacement policy$).$ Furthermore, every one of these arrays is physically distributed into multiple sub$-$arrays $($one per way$)$ that can be individually accessed; for example, a four$-$way set associative least recently used $($LRU$)$ cache would have four data sub$-$arrays, four tag sub$-$arrays, and four replacement sub$-$arrays. We assume that the replacement sub$-$arrays are accessed once per access when the LRU replacement policy is used, and once per miss if the first$-$in$,$ first$-$out $($FIFO$)$ replacement policy is used. It is not needed when a random replacement policy is used. For a specific cache, it was determined that the accesses to the different arrays have the following power consumption weights:

Estimate the cache power usage $($in power units$)$ for the following configurations. We assume the cache is four$-$way set associative. Main memory access power$-$albeit important$-$is not considered here. Provide answers for the LRU, FIFO, and random replacement policies.

a$)$ A cache read hit. All arrays are read simultaneously.

b$)$ Repeat part $($a$)$ for a cache read miss.

c$)$ Repeat part $($a$)$ assuming that the cache access is split across two cycles. In the first cycle, all the tag sub$-$arrays are accessed. In the second cycle, only the sub$-$array whose tag matched will be accessed.

d$)$ Repeat part $($c$)$ for a cache read miss $($no data array accesses in the second cycle$).$