16 is A because you would put a period after Ave because it is abbreviated .
17 is B because you put a comma after the city and dont put anything with the state. for example Defuniak Springs, FL
18 should be Your math facts, Carly, need much more drill. you are directly speaking to Carly. so Carly would be the appositive in the appositive phrase
19 is the first one. you put a comma after the day on a date. example May 5, 2018 and when you state what day it is then there is a comma there. example Monday, May 5, 2018.