Two boys A and B weighing 60 kg and 40 kg respectively,

Two boys A and B weighing 60 kg and 40 kg respectively, climb on a staircase each carrying a load of 20 kg on their head. The staircase has 10 steps, each of height 50 cm. If A takes 20 s to climb and B takes 10 s to climb, then
(i) who possesses greater power?
(ii) find the ratio of their powers.