Consider a two-level memory hierarchy made of L1 and L2 data caches. Assume that both caches use write-back policy on write hit and both have the same block size. List the actions taken in response to the following events:

a. An L1 cache miss when the caches are organized in an inclusive hierarchy.

b. An L1 cache miss when the caches are organized in an exclusive hierarchy.

c. In both parts (a) and (b), consider the possibility that the evicted line might be clean or dirty.