An electric bulb has a filament of surface area 20 $c{m}^2$.The filament is raised to a temperature of 1727 $°C$.When a current passes through it. If Stefan’s constant is $5.7\times {10}^{-8}W/m^2{K}^4$  and the emissivity of the filament is 0.5, the electric power (in W) being consumed to maintain this temperature is