Explanation:
This is a good example of Doppler effect
Given
Source velocity Vs=20m/s
Apparent frequency Fa= 5.2 Hz
Recall speed of sound V=340m/s
The frequency of the horn Fh=?
But mathematically Fh=(V-Vs/V)*Fa
(340-20)/340*5.2=4.89Hz
Answer:ITS B
Explanation: TOOK DA TEST AND GOT IT RIGHT NO CAP YOUR WELCOME
Ozone gas is made up of oxygen molecules that have three atoms. it exists in polluted air and ozone layer. Ozone layer is formed in stratosphere(part of atmosphere).
Before going to answer this question, first we have to understand centripetal force.
The centripetal force is the force which is required to keep the body along its circular path.The direction of the force is along the radius and towards the centre.

Here m is the mass of the body,v is the velocity of the body and r is the radius of the circular path.
When a body moves in a circular path,its velocity at any point is the tangent drawn at that point.
As centripetal force acts along the radius, it must be perpendicular to the velocity of the body.
Hence the correct answer to the question is- It acts perpendicular to the velocity and is directed toward the center of the circle.