A machine rated as 150 W, changes the velocity of a 10 kg mass from 4 ms^(-1)" and "10 ms^(-1) in 4s. The efficiency of the machine nearly is

A machine rated as 150 W, changes the velocity of a 10 kg mass from 4

1.	A machine rated as 150 W, changes the velocity of a 10 kg mass from 4 ms^(-1)" and "10 ms^(-1) in 4s. The efficiency of the machine nearly is
Answer» `70%` `30%` `50%` `40%` ANSWER :A