A windmill is taking advantage of strong air currents in order to produce electrical energy. On a typical day the wind speed is around 20 mph and in that speed the windmill produces 600 kw/h (kilowatts per hour). On a stormy day a windmill produces 20% more energy. How much kw/h can three windmills produce in two hours on a stormy day?  Pick one.
A) 2880.  B) 4320.  C) 5780.  D) 5760.  E) 6380.
Efficiency per machine = 600 watt/hr   Efficiency due to increase in wind speed = 600*120% =&gt; 720 watt/hr   Production by each machine in 2 hours is  720*2= 
<gadget id="calculator"> 720*2</gadget>
<output>1_440</output>
&gt; 1440 watt   Production by 3 machines=&gt; 1440 watt * 3 = 4320 watt   Answer will be (4320.)
<result>B</result>
A windmill is taking advantage of strong air currents in order to produce electrical energy. On a typical day the wind speed is around 20 mph and in that speed the windmill produces 600 kw/h (kilowatts per hour). On a stormy day a windmill produces 20% more energy. How much kw/h can three windmills produce in two hours on a stormy day?