Answer:
minimum frequency = 170 Hz
Explanation:
given data
One path long = 20 m
second path long = 21 m
speed of sound = 340 m/s
solution
we get here destructive phase that is path difference of minimum 
here λ is the wavelength of the wave
so path difference will be
21 - 20 =
λ = 2 m
and
velocity that is express as
velocity = frequency × wavelength .............1
frequency = 
minimum frequency = 170 Hz
When light passes from a faster medium into a slower medium, light will be refracted toward a line drawn perpendicular to the point of refraction. <em>(B)</em>
The forward force you exert on the fish and your backward action will allow you to reach the shore.
<h3>
Newton's third law of motion</h3>
Newton's third law of motion states that for every action, there is an equal and opposite reaction.
Fa = -Fb
Let's assume the fish is held in the hook, this will give you the opportunity to throw the fish forward while still holding it.
When the the fish is thrown forward, you will move backwards with an equal force based on Newton's third law. Your backward momentum towards the shore will help to maintain equal linear momentum between you and the fish.
Thus, this forward force of the fish and your backward action will allow you to reach the shore.
Learn more Newton's third law of motion here: brainly.com/question/25998091
