Answer:
1 : 2 cm/km or 
One cm represents 2 km.
Explanation:
If 3 cm represents 6 km on the earth, the ratio to consider is: 3 : 6 cm/km which is the same as:
1 : 2 cm/km or 
One cm represents 2 km.
Answer:
It is not a property of light. It is your eyes and brain.
Specifically, the three kinds of cone cells in our eye that are sensitive to different ranges of the electromagnetic spectrum. The fact that there are three means that color is three dimensional, and is the reason the pure colors form a circle even though the spectrum of wavelengths is linear.
Visible light is part of the electromagnetic spectrum; light waves of different frequencies and wavelengths are distinguished as colors by the human eye. A prism can separate the colors of white light (dispersion) because different frequencies of light have different refractive indices for a given material.
This is weird.
All three 'choices' are true.
Line um up. (a) shows how to solve the problem. (b) does it. and (c) is the answer.
Sure what do u need help with