Drop "moves" from the list for a moment.
You can also drop "stops moving", because that's included in "changes speed"
(from something to zero).
When an object changes speed or changes direction, that's called "acceleration".
I dropped the first one from the list, because an object can be moving,
and as long as it's speed is constant and it's moving in a straight line,
there's no acceleration.
I think you meant to say "starts moving". That's a change of speed (from zero
to something), so it's also acceleration.
Answer: Doppler Effect
Doppler Effect can be described as the change in
wavelength of a wave like upward shift in frequency for an object whom is
approaching and an apparent
downward shift in frequency for observers from whom the source is receding. This effect can be observed when a boat moves through the water then
the waves in front bunch up while the waves behind the boat spread out.
To solve this problem we will apply the concepts related to pressure, depending on the product between the density of the fluid, the gravity and the depth / height at which it is located.
For mercury, density, gravity and height are defined as
For the air the defined properties would be
We have for equilibrium that
Replacing,
Rearranging to find 
Therefore the elevation of the mountain top is 9400ft
Answer:
The solute is oxygen
The solvent is water
Explanation:
A solvent is any chemical substance that dissolves other chemical substances, while a solute refers to any chemical substance that dissolves in other chemical substances. The best way to know when a chemical substance dissolves in another chemical substance is when a solid or gas dissolves in water. The solid or the gas can now be referred to as the solute and it will be shown to be in the the aqueous state, while the solvent is usually shown to be in the liquid state in any chemical equation.
Let us use the particular example of the dissolution of oxygen gas in water as shown below;
O2(g) + H2O(l)⇄O2(aq) + H2O(l)
The aqueous oxygen is the solute while the liquid water is the solvent.
Also, the substance having a smaller mass must be the solute and the substance having the larger mass must be the solvent.
