How to calculate cache size?
1) If the cache is direct-mapped (i.e. 1 way) of 16 words, its size (excluding tags) is 16*4=64 bytes.
Line length does not matter.

2) There is a mismatch between "A address bits" and "tag size in Bytes"

Each tag contains :


A validity bit
The portion of addresses not indexed in the cache.
Usually some history bits for the various cache replacement algorithms (LRU, PLRU), used on multiways caches.


Each cache way size is (in bytes) : 4(bytes per word)*L(line size)*S(sets)


From the A address bits , you must place (A-ln2(L)-ln2(S)-2) address bits in the tags.
There is 1 tag per cache line. So there is W(ways) * S(sets) tags in your cache.


Even if question 2) is about the cache described in question 1), you cannot answer without knowing the number of address bits.