concept about kinematics and work?

A box laid on the ground with an initial speed v slides up a rough Inclined ramp until reaching a maximum height h above the ground. After that, it starts to slide down the ramp again. The final speed when it reaches its initial position on the ground is v'. What is correct:
a. Speed v' is less than speed v.
b. Speed v' is dependent on the object's mass
c. Total work done on box as it moves from ground to its max height is equal to the total work done on the box as it moves from its max height to ground
d. a and b are correct
e. all of the above are correct

answer is a, but why not b and c?

The answer c is incorrect because work done against friction always reduces the kinetic energy of the box whether it goes up or down, unlike the work done by gravity which increases the kinetic energy of box when it comes down and reduces it when it goes up.

B is wrong because the acceleration due to force of friction is independent of mass of the object. It can depend on mass provided the frictional force is velocity dependent and the object reaches terminal velocity. This is notexplicitlyy given in the problem.

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