unit of distance white, yellow, or black road markings guardrails or fencing signs indicating the distance road signs indicating the direction trees or other vegetation buildings, houses, or other structures in the background
mile which has unit of distance mile which has white, yellow, or black road markings mile which has guardrails or fencing mile which has signs indicating the distance mile which has road signs indicating the direction mile which has trees or other vegetation mile which has buildings, houses, or other structures in the background