Solve it in excel

Explain to me how to do this using Excel

I have just purchased (at time 0 ) a new car for $12,000. The cost of maintaining a car during a year depends on the age of the car at the beginning of the year, as given in Table 1. To avoid the high maintenance costs associated with an older car, 1 may trade in my car at the time of trade-in (see Table 2) To simplify computations, we assume that any time it costs $12,000 to purchase a new car. Determine a replacement policy that minimizes the net cost of owning and operating a car for the next 5 years. Table 1 Table 2