In physical science, there are two types of quantity: scalar and vector. While scalar quantities only include the magnitude, vector quantities include both the magnitude and the direction. Displacement is an example of vector quantities. Therefore, it includes magnitude and direction.
Answer:Theoretical Discussion
The diffraction of classical waves refers to the phenomenon wherein the waves encounter an obstacle that fragments the wave into components that interfere with one another. Interference simply means that the wave fronts add together to make a new wave which can be significantly different than the original wave. For example, a pair of sine waves having the same amplitude, but being 180◦ out of phase will sum to zero, since everywhere one is positive, the other is negative by an equal amount.
The answer to this question would be A. Interference. This is because when two sounds with slightly different frequencies creates a periodic variation in volume.
ANSWER:
250 J
STEP-BY-STEP EXPLANATION:
F = 20N is required to stretch the spring by 4 meters
We know that the force is equal to:

We solve for k (spring constant):

The work done in stretching the spring is given by the following equation (in this case the stretch is 10 meters:

The work required is 250 joules.
The correct answer to this problem would be that like poles repel and unlike poles attract.
N and N poles repel
S and S poles repel
N and S poles attract
S and N poles attract
Answer: D) like poles repel each other. unlike poles attract each other
I hope this helps!