[tex]h=14 \ m \\ m=350 \ kg \\ t=20 \ sec \\ g=10 \ N/kg \\ \bold{a)} \ \boxed{L=F \cdot h} \\ F=G=m \cdot g=350 \ kg \cdot 10 \ N/kg =3 \ 500 \ N \\ L=3 \ 500 \ N \cdot 14 \ m \\ \Rightarrow \boxed{\bold{L=49 \ 000 \ J=\boxed{\bold{49 \ kJ}}}} \\ \\ \bold{b)} \ \boxed{P=\frac{L}{t}} \\ P=\frac{49 \ 000 \ J}{20 \ sec} \\ \Rightarrow \boxed{\bold{P=2450 \ W}}[/tex]
