Water molecules are highly packed and are always near each other.
Nucleus ,endoplasmic reticulum
The person is called a wildlife biologist.
I can't see the picture, but in general, I believe it is in dropping from the first energy level above the ground state, to the ground state.
If the difference in electronegativtiy for the atoms in a bond are greater than 0.4,we consider the bond polar, if the electronegativity is less than 0.4, we consider it non polar. if there are no polar bonds, the molecule is non polar.