Answer
$n = 1.79 \times 10^{29} m^{-3}$
Work Step by Step
From the Fermi Energy Equation
$E_F = An^{2/3}$
Rearrange the equation
$n = [\frac{E_F}{A}]^{3/2} $
Where $E_F = 11.6eV$
and $A = 3.65 \times 10^{-19} m^2.eV$
Solve for n
$n = [\frac{11.6eV}{3.65 \times 10^{-19} m^2.eV}]^{3/2} $
$n = 1.79 \times 10^{29} m^{-3}$
