c
$V_T=\frac{2 g}{9} \frac{R^2\left[\rho_B-\rho_L\right]}{\eta}$
$\Rightarrow V_T=\frac{2}{9} \times \frac{10 \times\left(10^{-4}\right)^2}{9.8 \times 10^{-6}}\left[10^5-10^3\right]$
$\Rightarrow V_T=224.5$
when ball fall from height ($h$)
$\mathrm{V}=\sqrt{2 \mathrm{gh}}$
$\mathrm{h}=\left(\frac{\mathrm{V}^2}{2 \mathrm{~g}}\right)=2518 \mathrm{~m}$