The energy supplied to four ventilation fans and the energy dissipated during their operation are recorded below.
| Ventilation fan | Total energy input in J\mathrm{J}J | Dissipated energy in J\mathrm{J}J |
|---|---|---|
| W | 500 | 70 |
| X | 800 | 144 |
| Y | 600 | 90 |
| Z | 900 | 180 |
Which ventilation fan operates with an efficiency of 82%?
ventilation fan Y
ventilation fan X
ventilation fan W
ventilation fan Z