What is the -d on java command line.

Consider a direct-mapped cache with 216 words in main memory. the cache has 16 blocks of 8 words each. it is a word-addressable computer (rather than a byte-addressable computer which we normally discuss). (a) how many blocks of main memory are there? (b) what is the format of a memory address as seen by the cache, that is, what are the sizes of the tag, cache block, and block offset fields (if they apply)? (c) to which cache block will the memory reference db6316 map?