<h2>
Answer:</h2><h3>
<em><u>Alexander Graham Bell</u></em></h3><h2>
Explanation:</h2>
Alexander Graham Bell is often credited as the inventor of the telephone since he was awarded the first successful patent.
A how our planets and moons formed
Answer:
Electric potential energy at the negative terminal: 
Explanation:
When a particle with charge
travels across a potential difference
, then its change in electric potential energy is

In this problem, we know that:
The particle is an electron, so its charge is

We also know that the positive terminal is at potential

While the negative terminal is at potential

Therefore, the potential difference (final minus initial) is

So, the change in potential energy of the electron is

This means that the electron when it is at the negative terminal has
of energy more than when it is at the positive terminal.
Since the potential at the positive terminal is 0, this means that the electric potential energy of the electron at the negative end is

Answer:
Approximately
.
Explanation:
The refractive index of the air
is approximately
.
Let
denote the refractive index of the glass block, and let
denote the angle of refraction in the glass. Let
denote the angle at which the light enters the glass block from the air.
By Snell's Law:
.
Rearrange the Snell's Law equation to obtain:
.
Hence:
.
In other words, the angle of refraction in the glass would be approximately
.