On a planimetric map, the is used to determine the actual distance between two points.

The answer in this question is scale. The scale is used to determine the actual distance between two points in a planimetric map. This map only represents the horizontal position of features. This is also called by others as the line map.  This is usually consisted of man-made and natural features. These are from aerial shots by the use of modern technology. This map’s common features are street and water centerlines, sidewalks, culverts, utility lines, building footprints and vegetation. Sometimes, there are also other useful data attached in this map like titles of the properties, owner, assessed value, etc. It is because of these, this map becomes a storage of valuable data which can be easily and quickly accessed. 

grav potential energy

scattering of light by tiny particles in air to produce the colors we see on sky, is dependent on the following factors:

(i) wavelength of light

(ii) size of the scattering particle  

(iii) distance traveled by light through the atmosphere.

according to rayleigh's law of scattering, the amount of scattering is inversely proportional to the fourth power of its wavelength. shorter the wavelength, greater is its scattering. hence violet/blue light is scattered more than red.

sun's light is a composite light ( visible light) with wavelengths in the range 400 nm (violet) to 700 nm (red). as sunlight passes through our atmosphere, the molecules of air scatter light according to their wavelengths. during sunrise and sunset, the sun's position is below the horizon. hence light from the sun travels a greater distance in the atmosphere when compared to its position a noon.

as sunlight enters the earth's atmosphere, blue light is scattered away and at the end of its journey in the sky, only red and orange wavelengths remain in the beam.

hence at sunrise and sunset, the sky appears reddish orange.