what is the amount of force this student had to apply?

In order to calculate the force applied, let's use the work formula below:
[tex]W=F\cdot d[/tex]Where W is the work in Joules, F is the force in Newtons and d is the distance in meters.
So, for W = 2000 J and d = 10 m, we have:
[tex]\begin{gathered} 2000=F\cdot10 \\ F=\frac{2000}{10} \\ F=200\text{ N} \end{gathered}[/tex]Therefore the applied force is 200 N.