Physics
The blue colour of sky is due to

Scattering of shorter wavelengths of sunlight in the atmosphere
Reflection of sunlight
Refraction of sunlight
Scattering of longer wavelengths of sunlight in the atmosphere

ANSWER DOWNLOAD EXAMIANS APP

Physics
It is easier to roll a stone up a sloping road than to lift it vertical upwards because

Work done in rolling is more than in lifting.
Work done in lifting the stone is equal to rolling it.
Work done in both is same but the rate of doing work is less in rolling.
Work done in rolling a stone is less than in lifting it.

ANSWER DOWNLOAD EXAMIANS APP