Answer: 27.21 V
Explanation:
The <u>electric potential</u>
due to a point charge is expressed as:

Where:
is the <u>electric constant</u>
is the <u>electric charge of the hydrogen nucleus</u>, which is positive
is the <u>distance</u>
Rewritting the equation with the known values:

Finally:
A wall uses diffuse reflection while a mirror uses specular reflection. For example, when parallel light rays enter a mirror, they remain parallel when exiting the mirror, allowing you to see a reflection of the light rays. On the contrary, when incident light rays enter a wall which is painted, the rays scatter, not allowing you to see anything but a painted wall.
Answer: Permanent magnets consist of multiple "ferromagnetic materials" I think that might be the answer, there weren't really any choices for me to choose from.