Explanation:
Kevlar is a fiber which is used in making of bullet proof vests and armors. It is a co-polymer which is formed by condensing two organic molecules 1,4-phenylene-diamine and terephthaloyl chloride.
![NH_2C_6H_4NH_2+Cl-(CO)-C_6H_4-(CO)-Cl\xrightarrow[-2HCl]{ }](https://tex.z-dn.net/?f=NH_2C_6H_4NH_2%2BCl-%28CO%29-C_6H_4-%28CO%29-Cl%5Cxrightarrow%5B-2HCl%5D%7B%20%7D%20)

For Structure refer to image attached.
Answer: because a mole is based on Avogrado's number, which is 6.02 x 10²³ particles. It isn't possible to directly count that many particles at a time.
Since Alai is hitting each with a hammer, the physical property which he must be comparing on the two materials must be hardness. Solubility can be tested when you put them in a solvent. Odor can be tested with smell. Conductivity can be tested with electricity. Hardness can be tested with its resistance to the force that hits it.
Can you give more information?
Option d: copper.
Because copper is an element, not a mixture.