#### Answer

$v_{\circ}=7.45km/s$

#### Work Step by Step

We know that
$v_{\circ}=\sqrt{\frac{GM_e}{h+r_e}}$
We plug in the known values to obtain:
$\implies v_{\circ}=\sqrt{\frac{66.73(10^{-12})\times 5.97(10^{24})}{8(10^5)+6.378(10^6)}}$
This simplifies to:
$v_{\circ}=7453.6m/s=7.45km/s$