The doppler effect.
You are welcome.
<span>The velocity of light is by far the greatest in air. There is nothing in air to stop or impede the movement of light in air. When light travels in air it will not stop unless running into clouds, smoke, smoke, droplets, or impurities. Any other substance is harder for light to travel through.</span>
I believe the correct answer from the choices listed above is option B. The function of the pulley in this situation is to change the direction of the input force. <span> The </span>pulley<span> simply turns a force in one direction into a force in another direction. Hope this answers the question. Have a nice day.</span>