In a similar way we can now calculate the 150 m buffer around the roads.
1. Style the roads layer. Use these classes:
0: no roads
1: dirt road
2. Repeat the steps used to calculate the zones of 150 m around the houses, but use the roads layer as the Input layer and name the output roads150m.tif.3. Style the Boolean map. Make the True pixels green and the False pixels red.