prize7-9, Exercise 3: How a digital map can mislead

Model answer (example answers; others are possible):

1. Out-of-date data.
   Problem: a road has been closed, a bridge has a new weight limit, or a business has moved, but the map still shows the old situation.
   Detection: check the date of the imagery or the "last updated" note, compare with a second source, look for signs and local reports, and watch the road ahead rather than the screen alone.

2. Unsuitable route choice.
   Problem: a navigation app picks the shortest route, which may be an unsuitable track, a narrow lane or a road that is unsafe for a large vehicle.
   Detection: look at the route on the overview map, check road types and restrictions, and use a service or settings designed for your vehicle.

3. Missing or biased data.
   Problem: areas with few contributors or little commercial interest may have gaps.
   Detection: compare with another map and with local knowledge.

4. Projection or scale.
   Problem: Web Mercator exaggerates the size of high-latitude places when zoomed out.
   Detection: compare with a globe or an equal-area map.

Habit: treat a screen map as a model made by a company or community, and check it against the ground when the stakes are high.