PLEASE HELP!!!
If an airplane were flying west at 100 km/hr and encountered a strong gale blowing east at 100 km/hr, what would be the plane's velocity relative to the ground?
Explanation: As a vector, the plane's velocity is 100 km/h (west) - 100 km/h (east) = 0 km/m. To an observer on the ground, the plane will be standing still.