Answer:
its C! I just finished the test on edg :)
Answer:
The value is 
Explanation:
From the question we are told that
The height of the water is 
The density of oil is 
The height of oil is 
Given that both arms of the tube are open then the pressure on both side is the same
So

=> Here

where
is the density of water with value 
and
is the atmospheric pressure
and

=> 
=> 
=> 
=> 
The difference in height is evaluated as


Answer:
The pressure on the ground is about 9779.5 Pascal.
The pressure can be reduced by distributing the weight over a larger area using, for example, a thin plate with an area larger than the circular area of the barrel's bottom side. See more details further below.
Explanation:
Start with the formula for pressure
(pressure P) = (Force F) / (Area A)
In order to determine the pressure the barrel exerts on the floor area, we need the calculate the its weight first

where m is the mass of the barrel and g the gravitational acceleration. We can estimate this mass using the volume of a cylinder with radius 30 cm and height 1m, the density of the water, and the assumption that the container mass is negligible:

The density of water is 997 kg/m^3, so the mass of the barrel is:

and so the weight is

and so the pressure is

This answers the first part of the question.
The second part of the question asks for ways to reduce the above pressure without changing the amount of water. Since the pressure is directly proportional to the weight (determined by the water) and indirectly proportional to the area, changing the area offers itself here. Specifically, we could insert a thin plate (of negligible additional weight) to spread the weight of the barrel over a larger area. Alternatively, the barrel could be reshaped (if this is allowed) into one with a larger diameter (and smaller height), which would achieve a reduction of the pressure.
It all depends on what kind of wave, and what kind of medium.
For mechanical waves, like sound and earthquakes, the speed
is determined by the mechanical properties of the medium, like
density and stiffness.
For electromagnetic waves, like radio and light, the speed is
determined by the electrical properties of the medium, like
magnetic permeability and electrostatic permittivity.
That's a big part of the reason why sound and light travel
at different speeds through air, water, and jello.
D) the ability to make things happen
Explanation:
Energy is simply defined as the ability to do work or to make things happen. Energy is important to all aspects of living and non-living things. Based on the law of conservation of energy "energy can neither be created nor destroyed but can be transformed from one form to another".
Different forms of energy exists such as heat, thermal, chemical, mechanical, sound, electrical, e.t.c
Learn more:
Energy brainly.com/question/8727665
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