Question

The map shown is scale of 1:50 000

Answer 1

See the attached figure to better understand the problem

Part 1) 
using  a graph tool
the distance on the map from M to L  along a straight line is 5.8 cms

part 2) Calculate the actual distance in kilometers from L to M

we know that
the scale is 1:50 000
that means
1 cm on the map is in the actual-----> 50000 cm-----> 500 m-----> 0.5 km
so
if 1 cm on the map is--------> 0.5 km in the actual
 5.8 cm on the map is-------> X km
x=5.8*0.5-----> x=2.9 km

the answer Part 2) is
the actual distance in kilometers from L to M is 2.9 km

Part 3) The actual distance two points is 4.5 km calculate the number of centimeters that should be used to represent the distance one the map

if 1 cm on the map is--------> 0.5 km in the actual
 X cm--------------------------->  4.5 km
x=4.5/0.5-----> x=9 cm

the answer Part 3) is 9 cm