Answer:
12.5 cm
Explanation:
The ratio of map distance to ground distance is the same at any distance:
(map distance)/(ground distance) = (5 cm)/(2 km) = (x)/(5 km)
Multiply by 5 km and you have ...
x = (5 cm)(5/2) = 12.5 cm
The ground distance of 5 km is represented by 12.5 cm on the map.