The garden club earned $15 per hour by weeding neighborhood gardens for t hours. A generous donor has agreed to double their earnings. How much did the garden club earn in all?

Asales representative from a local radio station is trying to convince the owner of a small fitness club to advertise on her station. the representative says that if the owner begins advertising on the station today, the club's total number of members will grow exponentially each month. she uses the given expression to model the number of club members, in hundreds, after advertising for t months.