At the end of the second exon, the sequence AAA codes for lysine; however, the next cassette of 3 letters, GGT, is not a codon. In the space provided explain why not.

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