What is the advantage of R.F.?

Explain Magnetic declination with the help of a diagram.

What is a Scale? Name the main methods of representing the scale of a map.

Convert the following statements into R.F.

(a) 25 cm on the map = 5 km on ground.
(b) 2½ inches on the map = 5 miles on ground.
(c) 7 cm on the map = 63000 metres on ground.
(d) 5 cm = 500 metres.
(e) 15 cm = 6 km.