R1 can be configured with three static routes to reach all of the remote networks in the example topology. However, R1 is a stub router because it is only connected to R2. Therefore, it would be more efficient to configure a default static route.
The example in the figure configures a default static route on R1. With the configuration shown in the example, any packets not matching more specific route entries are forwarded to 172.16.2.2.