G=mg=>m=G/g=16680/9.8=1702 kg
p=mv=>v=p/m=54400/1702=32 m/s
Answer : Capacitors
Explanation : Capacitors are normally placed on transmission or distribution lines when to reduce inductive reactance.
This is because it enhances electromechanical and voltage stability , limit voltage dips at network nodes and reduces the power loss.
So, we can say that inductive reactance normally replace by the capacitors.
F=-ks
F=-(390)(.45)
F=-175.5 N
Work=force x displacement
Work= 175.5(0.45)
Work= 78.98 J
Work = ∆E =78.98 J
Answer=79J (first option)