if a gold atom is considered to be a cube with sides 2.5*10^

if a gold atom is considered to be a cube with sides 2.5*10^-9m.Hom many gold atoms could stack on top of one another in gold foil with a thickness of 1.0*10^-7?
on the average 1.0kg of aluminium consist of 2.2*10^25 atoms.How many atoms would there be in a block of aluminum 10cm by 1.2cm by 15.6cm,if the deusity of aluminum is 2.7g/cm^2,or2.7*10^3kg/m^3?