Answer is: C.) 4.10 m.
m(AgClO₄) = 75,2 g.
n(AgClO₄) = m(AgClO₄) ÷ M(AgClO₄).
n(AgClO₄) = 75,2 g ÷ 207,31 g/mol.
n(AgClO₄) = 0,362 mol.
m(C₆H₆) = 885 g ÷ 1000 g/kg = 0,885 kg.
b(solution) = n(AgClO₄) ÷ m(C₆H₆).
b(solution) = 0,362 mol ÷ 0,885 kg.
b(solution) = 0,41 mol/kg.