Blue colour of the sky is due to

In heavy fog,the yellow colour of a vehicle's headlight is preferred compared to other colours. Why?

During the scattering of light, the amount of scattering is inversely proportional to the . . . . . . of the wavelength of light.

Sir $C$.$V$. Raman was awarded the Nobel Prize in Physics for his work on:

If the scattering intensity of a liquid is $8 \text{ units}$ at a wavelength of $500 \text{ nm}$, then the scattering intensity at a wavelength of $400 \text{ nm}$ will be approximately: (in $\text{ units}$)

Frequencies of light incident on a system of scattering particles are in the ratio of $1: 2$. Then, the intensity of scattered light in a particular direction is