Answer:
Explanation:
We shall apply law of refraction which is as follows
sin i / sinr = μ , where i is angle of incidence , r is angle of refraction and μ is refractive index
here i = θa = 22.5°
r = θb
μ = 1.77
sin22.5 / sinθb = 1.77
.3826 / sinθb = 1.77
sinθb = .216
θb = 12.5 °.
The calculated time is 6 seconds.
Time is defined by physicists as the flow of events from the past through the present and into the future. In essence, a system is timeless if it is unchanging. When describing events that take place in three-dimensional space, time can be thought of as the fourth dimension of reality. Even if time isn't directly connected to energy, it is undoubtedly connected to many other components of energy. For instance, the movement of energy across the universe can affect the direction of time (from the past to the future).
V= 2 m/s
d=12 m
t=?
we know that velocity=displacement / time
time= displacement / velocity
= 12/2
=6 seconds
the calculated time is 6 seconds.
Learn more about time here-
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The force of static friction acting on the boy is 333 Newtons.
Hence, option (d) 333N is the correct answer.
Given the data in the question;
- Weight of boy;

- Coefficient of static friction;

Force of static friction acting on the boy; 
<h3>Friction</h3>
Friction is simply referred as the resistance an object experience when moving or trying to move over another object. It can either by dynamic or static.
Static friction is the resistance experienced by a body at rest.
Coefficient of friction is the measure of how easily a body moves in relation to the other.
Static friction is expressed as;

Where
is the normal force and
is the coefficient of static friction.
We substitute our given values into the equation above

The force of static friction acting on the boy is 333 Newtons.
Hence, option (d) 333N is the correct answer.
Learn more friction: brainly.com/question/17237604