The difference of three fifths of N and six.

Which of the following is most likely the next step in the series? a3z, b6y, c9x, d12w, е15v, f18u

Any is very appreciated! (picture is provided below)not sure how to do this at all won't lie

Do more republicans (group a) than democrats (group b) favor a bill to make it easier for someone to own a firearm? two hundred republicans and two hundred democrats were asked if they favored a bill that made it easier for someone to own a firearm. how would we write the alternative hypothesis?