The work spent during a move is given by the Definition of Word:
[tex]T=F\Delta S \\ T=ma\Delta S[/tex]
Analizyng the units, we have:
[tex]J=kg* \frac{m}{s^2} *m \\ \boxed {J= \frac{kg*m^2}{s^2} }[/tex]
Number 3
If you notice any mistake in my english, please let me know, because i am not native.