Some carpets have thin copper wires running through them. the student is less
likely to receive an electric shock after walking on this type of carpet.
suggest why.

Copper is a conductor and both carpet and floor are insulators. So the boy running on carpet doesn't feel current.

Explanation:

The boy is a conductor having flow of electrons in blood. While the same is the case with copper and carpet is non-conductor. It is useful to use copper wires in houses under carpets to facilitate the owner in both manners.  

See below.

Explanation:

Because copper is a very good conductor of electricity so it will likely conduct any electricity away from the person.

1. for the first question, we must find the mass of the anhydrous salt, mgso₄. the molar mass for mgso₄·7h₂o is 246.47 g/mol, while that of mgso₄ is 120.37 g/mol.7.834 g mgso₄·7h₂o * 1 mol mgso₄·7h₂o/246.47 g * 1 mol mgso₄/1 mol mgso₄·7h₂o * 20.37 g mgso₄/mol = 0.647 g mgso₄

2. mass of water = mass of sample - mass of anhydrous salemass of water = 7.834 - 0.647 = 7.19 gpercent water in hydrate = 7.19/7.834 * 100 = 91.74%