Answer:
b
Explanation:
A pure substance has a constant composition and cannot be separated into simpler substances by physical means. There are two types of pure substances: elements and compounds.
Well it breaks down into small parts
The differences in the properties of diamond and graphite is as a result of how their particles are arranged in space. This space arrangement leads to distinct crystal structures for the two compounds. In diamond, the carbon atoms are arranged in tetrahedral shape while in graphite the carbon atoms arrayed in planes.
Hope this helps :)
The quantity which is equivalent to the product of the absolute index of refraction of water and the speed of light in water system is the speed of light in vacuum.
<h3>What is the speed of light?</h3>
Speed of light is the rate of speed though the light travels. To find the speed of light in any medium, the following formula is used.

Here, (n) is the index of reaction and (c) is the speed of light in the vacuum. The speed of light in the vacuum is almost equal to the 3.0×10⁸ m/s.
Now the quantity which is equivalent to the product of the absolute index of refraction of water and the speed of light in water has to be find out.
The above formula can be written as,

Here, the product of index of refraction and speed of light is equal to the speed of light in vacuum. This will be true for water as well.
Thus, the quantity which is equivalent to the product of the absolute index of refraction of water and the speed of light in water system is the speed of light in vacuum.
Learn more about the speed of light here;
brainly.com/question/104425
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