Answer and Explanation:
Because metallic bonding involves delocalized electrons. It is described as a "<em>sea of electrons</em>", because the electrons are not confined around the nucleus of metal atoms, but they are delocalized: thay can be located in one nucleus and then in another neighbor atom. Thus, the electrons have more freedom to move from one part of the metal to another and electricity is well conducted.
Answer : The correct option is, 13.7 mole
Solution : Given,
Moles of
= 27.4 moles
The given balanced chemical reaction is,

From the balanced chemical reaction, we conclude that
As, 2 moles of
react with 1 moles of 
So, 27.4 moles of
react with
moles of 
Therefore, the number of moles of oxygen
required are, 13.7 moles
The usual units of density are g/cm.
You may have also seen g/mL used for density. Keep in mind that 1 cm = 1 mL.
The answer would be a bird eats seeds because that is what the parent has been feeding him.