Physics
Why two thin shirts can keep us warmer than a single thick shirt in winter ?

Air layer between two shirts behaves like insulating media
Air layer between two shirts works as good conductor
No radiation of heat takes place
Two thin shirts become thicker so prevent transmission of heat

ANSWER DOWNLOAD EXAMIANS APP

Physics
The blue colour of water in the sea is due to

Reflection of blue light by impurities in sea water
Absorption of other colours except blue by water molecules
Reflection of blue sky by sea water
Scattering of blue light by water molecules

ANSWER DOWNLOAD EXAMIANS APP