Chapter 13 - Kinetics of a Particle: Force and Acceleration - Section 13.7 - Central-Force Motion and Space Mechanics - Problems - Page 171: 115

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

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: $v_{\circ}=7453.6m/s=7.45km/s$