Answer:
400 N
Explanation:
By the law of friction,
is the maximum frictional force, 
is the coefficient of friction and 
is the reaction on the refrigerator. On a horizontal surface, the reaction is equal to the weight of the refrigerator.
While not moving, the fricition on the refrigerator is static friction. So, 
This is the maximum frictional force and is more than the applied horizontal force of 400 N. Frictional force cannot be more than the applied force, else it would actually pull the refrigerator backwards (a strange thing, if it were to happen). It is equal to the extent of the applied force because the applied force is not enough to overcome the maximum.
Hence the frictional force is 400 N.
PS: Note that we do not use the coefficient of kinetic friction because applied force could not overcome the static friction.
This is false. Your hypothesis, or prediction, is just that: a prediction. Saying its a failure will result in bias.
I would said A is the best option if i’m wrong sorry
The time taken is 1040 s.
<h3>What is speed?</h3>
The term speed refers to the rate at which the distance changes per unit time. This is why we define speed as the ratio of the distance to time for a body that is moving along a straight line.
Now;
We must first convert the distance to meters;
distance = 5.2km or 5200m
Speed = distance/time
time = distance/speed
time = 5200m/5 m/s
time = 1040 s
Learn more about speed:brainly.com/question/28224010
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