Physics
An egg sinks in soft water but floats in a concentrated solution of salt because

The density of salt solution exceeds the density of eggs
Water has high surface tension
Egg absorbs salt from the solution and expands
Albumin dissolves in salt solution and egg becomes lighter

ANSWER DOWNLOAD EXAMIANS APP

Physics
A white and smooth surface is

Bad absorber and bad reflector of heat
Good absorber and bad reflector of heat
Good absorber and good reflector of heat
Bad absorber and good reflector of heat

ANSWER DOWNLOAD EXAMIANS APP