<u>Answer:</u> The edge length of the unit cell is 0.461 nm
<u>Explanation:</u>
We are given:
Atomic radius of iridium = 0.163 nm
To calculate the edge length, we use the relation between the radius and edge length for FCC lattice:

Putting values in above equation, we get:

Hence, the edge length of the unit cell is 0.461 nm
the correct answer is option ( A ) Mixture
Explanation:
It is defined as the substance that is made by the combination of two or more different components. Or, we can say that it is created when solids liquids or gases mixed with one another. Hence, the correct option is, mixture.
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