RRB Group D 13-Dec-2018 Shift 2 Solved Paper

Energy Consumed is expressed in kilo Watt hour (kWh) or what we commonly call as unit.
Energy= Power× Time for getting Energy in "kilo Watt hour or unit", make Power in kilo Watts and Time in Hours).
So here,
Power= 800 Watts or 0.8 kilo Watts
Time= 3 hours
So Energy (in kWh or Unit)=0.8 kW×3 hour= 2.4 kWh or 2.4 unit