Please help asap for exams

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

Ann and betty together have $60 ann has $9 more than twice betty’s amount how much money dose each have

The marked price of an article is 25% above its selling price and the cost price is 30% less than its marked price . find the discount percent and gain percent. only a brainlest can solve it i will mark you brainlest