Question

please help three questions!:) god bless you!

1.
If you have a device that has an energy efficiency of 0.4 and you put in 100 units of energy, how many units of useful energy will you get out of it?
A. 0.4
B. 4
C. 40
2.
If we use energy more efficiently, we get more ______ from our energy.
A. useful work
B. heat
C. oil
3.
The human body has an energy efficiency of:
A. 5%
B. 50%
C. 75%
D. 100%

Answer 1

1. C

Answer 2

2.A