Definitely D. The brakes on a bike rub against the wheel. Not sure about the others.
The expression of the electric flux is

Here,
Q = Total charge enclosed in the closed surface
= Permittivity due to free space
Rearranging to find the charge,

Replacing with our values we have finally



The charge enclosed by the box is 0.1684nC
The sign of the charge can be decided by using the direction of the flux. The charge enclosed by the cube can be calculated by using the electric flux and the permitivity of free space.
Find refractive index first



Now






the height of the building is H=36 m.
<h3>What is The Law of Gravity?</h3>
According to Newton's law of gravity, every particle of matter in the universe is attracted to every other particle with a force that varies directly as the product of their masses and inversely as their distance from one another.
Properties of Gravity -
- It is a universal attractive force. It is directly proportional to the product of the masses of the two bodies.
- It obey inverse square law.
- It is the weakest force known in nature.
Examples of Gravity -
- The force that holds the gases in the sun.
- The force that causes a ball you throw in the air to come down again.
- The force that causes a car to coast downhill even when you aren't stepping on the gas.
v₀=0 m/s
H₀=0 m
g=10 m/s²
t=7,2 s
H - ?

H = 0 +0 × 7.2 + 10(7.2)²/2
H = 36m
to learn more about Gravity go to - brainly.com/question/12528243
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