Answer:
Force of static friction between the two surfaces
Explanation:
When two surfaces come into contact, they exert a force that resist the sliding of the two surfaces. This force is called static friction.
This force is given by the relation

Where,
μ - coefficient of static friction
η - normal force acting on the body
When a force acts on a body placed on a rough surface, it doesn't do any work if the applied force was less than the force of static friction.
So, in order to move the body, the applied force should be greater than the force of static friction.
Answer:
c.
Explanation:
they are all almost correct.
c is the only fully correct option
Answer:
Converted to an amount of energy equal to 4 million tons times the speed of light squared. ejected into space in a solar wind.
Explanation:
The 4 million tons of mass is converted to the amount of energy that is equal to 4 million tons times the speed of light squared. This energy moves from the sun with the help of solar winds and received by the planets present in the solar system. This solar energy moves in the form of solar radiation because there is no medium for propagation so that's why we can say that the mass is converted into energy that moves in the form of radiation in discrete packets.
Answer: 5.30m
Explanation:
depth of pool = 3.2 m
i = 67.75°
Using snell's law, we have,
n₁ × sin(i) = n₂ × 2 × sin(r)
n₁ = 1, n₂ =1.33, r= 44.09°
Hence,
Distance of Google from edge if pool is:
2.2 + d×tan(r) = 2.2 + (3.2 × tan(44.09°) =5.30m