1) The document discusses an experiment that measured the velocity profile over a rough flat surface at different locations along the surface (sections) and with varying mainstream air velocities. 2) The results showed that at a given location, velocity increased with increasing mainstream velocity. Additionally, boundary layer thickness increased with distance from the leading edge but decreased with increasing mainstream velocity. 3) In conclusion, the velocity over the rough surface was significantly influenced by the incoming air velocity, and boundary layer thickness varied inversely with mainstream velocity but directly with distance from the leading edge.