Answer:
a)
, b) 
Explanation:
a) The acceleration due to gravity inside the planet is:





b) The acceleration at the surface of the planet is:

The efficiency of the engine at the given useful energy and input energy is 28%.
The given parameters:
- <em>Input energy of the engine, = 125 J</em>
- <em>Useful energy of the engine, 35 J</em>
The efficiency of the engine is defined as the ratio of the output energy (useful energy) to the input energy and it is calculated as follows;

Thus, the efficiency of the engine at the given useful energy and input energy is 28%.
Learn more about efficiency of engine here: brainly.com/question/6751595
Answer:
Pressure of liquid in container is given by, P= height × density × acceleration of gravity.
At the lower storey, the height of the liquid from the open end is great, since height is directly proportional to pressure, the pressure exerted by liquid is maximum hence increase in velocity of flow.
Unlike the upper storey where the height of water is less hence the pressure exerted by the liquid is minimum which decreases the velocity / speed of liquid flow
Answer:
D.
Explanation:
This is the essence of “correlation does not imply causation”. When there is a common cause between two variables, then they will be correlated. This is part of the reasoning behind the less-known phrase, “ There is no correlation without causation ”.
Momentum and inertia,
Momentum=P. P=MV. M=mass and V=velocity. Mass is related to inertia so inertia=F. F=MA. A=acceleration.