A computer system with a word length of 32 bits has a 16 MB byte-addressable main memory and a 64 KB, 4-way set associative cache memory with a block size of 256 bytes. Consider the following four physical addresses represented in hexadecimal notation.

A1 = 0x42C8A4, A2 = 0x546888, A3 = 0x6A289C, A4 = 0x5E4880

Which one of the following is TRUE?

The size of the physical address space of a processor is $${2^P}$$ bytes. The word length is $${2^W}$$ bytes. The capacity of cache memory is $${2^N}$$ bytes. The size of each cache block is $${2^M}$$ words. For a $$K$$-way set-associative cache memory, the length (in number of bits) of the tag field is

The width of the physical address on a machine is $$40$$ bits. The width of the tag field in a $$512$$ $$KB$$ $$8$$-way set associative cache is _____________ bits.

A file system uses an in-memory cache to cache disk blocks. The miss rate of the cache is shown in the figure. The latency to read a block from the cache is $$1$$ $$ms$$ and to read a block from the disk is $$10$$ $$ms.$$ Assume that the cost of checking whether a block exists in the cache is negligible. Available cache sizes are in multiples of $$10$$ $$MB.$$

The smallest cache size required to ensure an average read latency of less than $$6$$ $$ms$$ is _________ $$MB.$$