What are structures without a present-day function called? a. homologous c. vestigial b. analogous d. extinct

C. Vestigial. 

A vestigial structure example in out bodies is the Appendix. We don't really need it, it just kind of "hangs out" in our bodies. We evolved to not need it. 

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Are you asking about a street map usage  if so here is your answer  a street map for a very limited area could simply be a bit map or a .jpg image.  but a more general map would probably store the streets as vectors.  but you shouldn't assume that there is one way to do it