Which of the following best describes a cause of wind? (points : 3) conduction of heat from earth's surface to the upper atmosphere earth's spin on its axis movement of air due to temperature differences movement of air due to different changes is water vapor content

C) movement of air due to temperature differences. warmer air closer to the ground has lower density, hence it rises up into the atmosphere. the cooler air from above rushes to take its place, giving rise to convection currents, causing 'winds' in the process.

The speed of the kid and the skateboard together is 0.723 m/s

Explanation:

Let the mass of the kid be

Let the mass of the skateboard be

The initial speed of the skateboard,

The initial horizontal speed of the boy as he jumps on the skateboard,

Let the speed of the kid and the skateboard together be v

According to the principle of conservation of momentum:

Substituting the appropriate values into  the given equation

36 = 49.8 v

v = 36/49.8

v = 0.723 m/s