A.
In order to calculate the kinetic energy of the box, we can use the formula below:
[tex]KE=\frac{mv^2}{2}[/tex]Where m is the mass and v is the velocity.
Using m = 12 kg and v = 3 m/s, we have:
[tex]\begin{gathered} KE=\frac{12\cdot3^2}{2} \\ KE=6\cdot9 \\ KE=54\text{ J} \end{gathered}[/tex]B.
The work done by Jim can be calculated with the formula below:
[tex]W=F\cdot d[/tex]Where F is the force and d is the distance.
The force applied is equal to the weight force of the box, so:
[tex]\begin{gathered} W=(m\cdot g)\cdot d \\ W=12\cdot9.8\cdot6 \\ W=705.6\text{ J} \end{gathered}[/tex]