If I'm correct, gold does not tarnish so C.
Answer: (b)
Explanation:
Given
Mass of box 
Applied force 
Friction force 
Box travels a distance of 
time taken 
Net unbalanced force 
Work done by the unbalanced force

Power developed by unbalanced force

Thus, option (b) is correct.
Answer:
<h2>2.08 hp</h2>
Explanation:
The power of the crane can be found by using the formula

f is the Force
d is the distance
t is the time taken
From the question we have

We have
power = 1600 W
But 1 W = 0.0013 hp
So 1600 = 2.08 hp
We have the final answer as
<h3>2.08 hp</h3>
Hope this helps you
22N to the right and 13N to the left
Forces are in opposite directions so you subtract the bigger force from the smaller force
Magnitude of force= 22N -13N
= 9N
net force direction is to the right