The top of insulated cylindrical container is covered by a disc having emissivity $0.6$ and thickness $1\, cm$. The temperature is maintained by circulating oil as shown in figure. If temperature of upper surface of disc is $127^o C$ and temperature of surrounding is $27^o C$, then the radiation loss to the surroundings will be (Take $\sigma = \frac{{17}}{3} \times {10^{ - 8}}W/{m^2}{K^4})$
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