Answer:
They combine if they have the same units
Explanation:
I am not quite sure what you mean by this question. I will try my best to answer this.
Velocities combine only if they both have the same units. The linear velocities have the unit meters per second. For example, a linear velocity and an angular velocity cannot combine together because angular velocity has a unit of radians per second.
Answer:
The velocity just before hitting the ground is 
Explanation:
From the question we are told that
The initial speed is 
The final speed is 
From the equations of motion we have that

Where s is the distance travelled which is the height of the cliff
So making it the subject of the the formula we have that

Where a is the acceleration due to gravity with a value 
So


Now we are told that was through horizontally with a speed of

Which implies that this would be its velocity horizontally through out the motion
Now it final velocity vertically can be mathematically evaluated as

Substituting values


The resultant final velocity is mathematically evaluated as

Substituting values


<span> Given the relationship between </span>wavelength<span> and </span>frequency<span> — the </span>higher<span>the </span>frequency<span>, the shorter the </span>wavelength<span> — it follows that short wavelengths are</span>more<span> energetic than long wavelengths.</span>