I think the correct answer from the choices listed above is option A. The direct cause of surface currents is the uneven heating. The uneven heating creates hot and cold areas which results to the creation of convective currents.
Radiowaves are electromagnetic waves and don't need a medium to travel through so B
Centripetal acceleration is the force acting on the body who's moving in a circular motion. It is still a force, which according to Newton's Second Law of Motion,
F = ma
F = (70 kg)(2)(9.81 m/s²)
F = 1373.4 N
<em>Thus, the answer is B.</em>
<span>Kinetic energy is energy that a body possesses by virtue of being in motion.
Think of a windmill...
Windmills use the winds energy in order to spin and in doing so creates energy for other things to be powered.
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the best option would be d.) examples of constructive erosion.