<h3><u>Answer;</u></h3>
A dense substance that is hard and incompressible
<h3><u>Explanation</u>;</h3>
- <em><u>Crystals are solids that are made up of particles such as molecules, atoms or ions, </u></em>which are arrange in a highly ordered microscopic structure, forming a crystal lattice which extends in all directions.
- Examples of crystals include<em><u> quartz,</u></em> that is made up of silicon (iV) oxide molecules that are arranged in a lattice,<u><em>table salt</em></u> is another example that is made up of sodium and chloride ions that are arranged in a lattice
- Crystals are very ordered, they may be made up of atoms of the same elements or atoms of different elements such as in the case of table salt.
Red is the answer in the blank
As per as the Multiplication rules of the significant figures, whenever any numbers in the decimals forms are multiplied or divided then result in mentioned in such a way so that the significant figures after the decimal will be same as that in the given least condition.
_______________________________
102900/12 = 8575
170 × 1.27 = 215.9
∴ (102,900 ÷ 12) + (170 × 1.27) = 8575 + 215.9
= 8790.9
Now, As per as Above rules, answer in correct significant figures will be = 8791.
It is supposed to protect the cell from it's surroundings, or from the outside.
