The magnitude of the source charge is 3 μC which generates 4286 N/C of the electric field. Option B is correct.
What does Gauss Law state?
It states that the electric flux across any closed surface is directly proportional to the net electric charge enclosed by the surface.

Where,
= electric force = 4286 N/C
= Coulomb constant = 
= charges = ?
= distance of separation = 2.5 m
Put the values in the formula,

Therefore, the magnitude of the source charge is 3 μC.
Learn more about Gauss's law:
brainly.com/question/1249602
like just try and try you gut it just trust me I'm a Wuman and you a man
Oil is less dense than water so it tends to float on the top of the water. Hope this Helps!
First of all, we need to convert the angular speed from rev/min into rev/s:

The angular acceleration is the variation of angular speed divided by the time:

And this is constant, so we can use the following equation to calculate the angle through which the engine has rotated:

so, 5 revolutions.
If it is completely elastic, you can calculate the velocity of the second ball from the kinetic energy
<span>v1 = velocity of #1 </span>
<span>v1' = velocity of #1 after collision </span>
<span>v2' = velocity of #2 after collision. </span>
<span>kinetic energy: v1^2 = v1' ^2 + v2' ^2 (1/2 and m cancel out) </span>
<span>5^2 = 4.35^2 + v2' ^2 </span>
<span>v2 = 2.46 m/s <--- ANSWER</span>