The number of cars sold weekly by a new automobile dealership grows according to a linear growth model. The first week the dealership sold three cars ( P0=3). The second week the dealership sold nine cars ( P1=9). Write the recursive formula for the number of cars sold, P, in the (n + 1)n week. P- Pn-1. Write the explicit formula for the number of cars sold, P, in the (n + 1)1n week. If this trend continues, how many cars will be sold in the fourth week?