The derivative of the function space as a function of time is equal to a function of speed as a function of time.
The velocity vector is given by the vector sum of the velocities of both axes.

If you notice any mistake in my english, please let me know, because I am not native.
Answer:
161.86 N
Explanation:
mass of box m= 55.0 kg
weight of the box, mg= 55×9.81
g here is acceleration due to gravity =9.81 m/sec^2
coefficient of friction between the box and the surface μ= 0.3
the friction force F_s= μmg= 0.3×55×9.81
=161.86 N
to move the ball horizontal force required is 161.86 N
Dropping it on a hard surface.
Answer:
the first one is Primary
the second one I think it's Mature but I don't know