Local phone numbers consist of seven numerals, the first three of which are common to many users. A small town's phone numbers all start with 313, 359, or 387. How many phone numbers are available?

b is the right answer

l' jhl jje f id bid b e iueb v jhdvb vh ei uf djbduv evb                                                                                                                                   8gfdgsfhjk.,l/ uh   dv eb b                            

the answer is a.

606.0 sq. in.

i got it down.