This question involves the concepts of the law of conservation of energy, kinetic energy, and potential energy.
The height of the hill is "166.76 m".
<h3>LAW OF CONSERVATION OF ENERGY:</h3>
According to the law of conservation of energy at the highest point of the roller coaster ride, that is, the hill, the whole (maximum) kinetic energy of the roller coaster is converted into its potential energy:

where,
- h = height of the hill = ?
= maximum velocity = 57.2 m/s
- g = acceleration due to gravity = 9.81 m/s²
Therefore,

<u>h = 166.76 m</u>
Learn more about the law of conservation of energy here:
brainly.com/question/101125
It is (A) for the first one and (B) for the second one.
Answer:

Explanation:
One of the first propulsion characteristics given in the example is that all engines are equal.
In this way if we have 4 engines running at the same time, it means that its capacity is 100%.
Under this premise, if 100% is found, the Jet is capable of reaching a speed of 8.7m / s ^ 2.
However, the question is, what would happen if 2.4 "Engines" now work.
To do this then we make a simple equivalence,
If 4 engines is the equivalent of 100%, when would it be 2.4 engines?

In this way it would mean that the body could be driven to 60% of its total.
So

Answer:

Explanation:
- We have to make a hollow sphere of inner radius
and outer radius
.
Then the mass of the material required to make such a sphere would be calculated as:
Total volume of the spherical shell:

And the volume of the hollow space in the sphere:

Therefore the net volume of material required to make the sphere:


- Now let the density of the of the material be
.
<u>Then the mass of the material used is:</u>

