Answer is: mass od zinc is 392,28 g.
N(Zn) = 3,6·10²⁴.
n(Zn) = N(Zn) ÷ Na.
n(Zn) = 3,6·10²⁴ ÷ 6·10²³ 1/mol.
n(Zn) = 6 mol.
m(Zn) = n(Zn) · M(Zn).
m(Zn) = 6 mol · 65,38 g/mol.
m(Zn) = 392,28 g.
Na - Avogadro number.
n - amount of substance.
M - molar mass.