An electrically neutral atom of beryllium has four protons.
which statement is true?
-there are four neutrons in the nucleus. -there is a charge of +4 on an atom of beryllium. -there is a charge of -4 on an atom of beryllium. -there are four electrons.

the density of gold = 19.3 g/cm3

the relation between density and mass and volume is

density = mass / volume

given :

mass of gold = 13 g

density = 13g / volume = 19.3

volume = 13 /19.3 = 0.67 cm^3

thus volume of gold nugget = 0.67 cm^3

you need to stop taking that class