Answer:

Explanation:
The potential produces by a point charge is given by:

Here, k is the Coulomb constant, q is the signed magnitude of the point charge and r is the distance between the charge and the point at which the electric potential is measured. Solving for q:

Answer:
The distance covered is 40 m and the displacement is 31,6m.
Explanation:
The distance covered is the sum of the two distances (10+30). The displacement is equal to the distance of the hipotenusa of the triangle that the two distances (10 m to north and 30m to east) create. Using the Pythagoras theorem the displacent is equal to the Square root of (30^2 +10^2) .
Answer:
you should sell your skateboards at $240
Explanation:
The price p to sell your skateboards for so that there is neither a shortage nor a surplus is the price that makes equal the quantity of sales and the quantity of supply, so p is equal to:
q (sales) = q (supply)
-3p + 700 = 2p - 500
700 + 500 = 2p + 3p
1200 = 5p
1200/5 = p
$240 = p