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Answer:</h2>
<u>c. Solstice</u> describes days when sun's rays directly hit Tropic of Cancer and Tropic of Capricorn.
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Explanation:</h2>
The solstices occur due to the declination of the Earth's orbital movement around the sun. During this declination, the axial tilt is 23.5°. Furthermore, solstice's occurrence is during time the sun's direction is overhead the moon.
In Northern hemisphere, the declination is towards Tropic of Cancer with the axial tilt of 23.5°N. It occurs on June 20 & 22 while in the south the normal period of occurrence is between December 20 and December 23. In the south, the solar declination hits Tropic of Capricorn at 23.5°S.
The correct answer is - Seafloor spreading at the mid-ocean ridge provides the mechanism for tectonic plate movement.
Harry Hess is one of the people that is most important when it comes to the proving and world wide acceptance of the continental drift theory.
Hess was very interested in the topic, and he was constantly looking for clues that would bring light to it and finally have a definite proof of it. While sailing through the Atlantic and doing some examinations, Hess noticed that there high mountains in the water, having flat peaks, and being arranged in an interesting manner. These underwater mountains, named guyouts, were the highest at a certain point, and than on both sides, as the distance was increasing they were becoming smaller and smaller.
What Hess stumbled upon was the seafloor spreading and how it works, and he recognized that quickly. He immediately went on to share what he discovered, that there's magma coming from bellow, solidifying and spreading, thus creating new crust while pushing the old crust away from the center, which is the reason why the continents are moving.
<em>Scientific method </em>is basically the process for experimentation used for observing– and is in any investigation in which a hypothesis is scientifically tested.