Answer
$9.3\times10^{3}km$
Work Step by Step
"g" is given by $g=\frac{GM}{R^{2}}$
or, $R=\sqrt (\frac{GM}{g})=\sqrt \frac{6.674\times10^{-11}\times5.974\times10^{24}}{1.62}=1.57\times10^{4}km$
Thus the height above the surface = $1.57\times10^{4}-6.371\times10^{3}=9.3\times10^{3}km$
