At the height h above the surface of earth, the value of g : (R is radius of the earth)

When height is 9R :

$g_h=g{\left(\frac{R}{R+h}\right)}^2\Rightarrow g_h=g{\left[\frac{R}{10R}\right]}^2=\frac{g}{100}$

$\frac{{\mathrm{g}}_{\mathrm{h}}}{\mathrm{g}}=\frac{1}{100}\Rightarrow {\mathrm{g}}_{\mathrm{h}}=1\mathrm{\%} \text{of }\mathrm{g} \text{at }\mathrm{h}=9\mathrm{R}$

When height is 64 km :

${\mathrm{g}}_{\mathrm{h}}=\mathrm{g}[1-\frac{2\mathrm{h}}{\mathrm{R}}]\Rightarrow \frac{{\mathrm{g}}_{\mathrm{h}}}{\mathrm{g}}=[1-\frac{64\times 2}{6410}]=\frac{98}{100}\text{;}$

$$\begin{gathered} \therefore \frac{\mathrm{\Delta g}}{\mathrm{g}}=-2\mathrm{\%} ; \\ \mathrm{when} \mathrm{height} \mathrm{is} 32 \mathrm{km} : \\ {\mathrm{g}}_{\mathrm{h}}=\mathrm{g}[1-\frac{2\times 32}{6400}]=\mathrm{g}\times \frac{99}{100} \end{gathered}$$

$\frac{{\mathrm{g}}_{\mathrm{h}}-\mathrm{g}}{\mathrm{g}}=\frac{-1}{100}\Rightarrow \frac{\mathrm{\Delta g}}{\mathrm{g}}=-1\mathrm{\%}$