One month, ava purchased a set of 35 stamps. each month, starting the second month, she purchased 3 more stamps for her collection. what is the explicit rule for the number of stamps in ava's collection after n months? enter your answer in the box.

Darcy deposited $390 into a savings account. as long as the account balance remains at or above $150, she does not have to pay a service fee for the account. for how many months can she withdraw $40 a month without having to pay service fees? a) 3 b) 5 c) 6 d) 9