If \(1.2 \times 10^{6} \mathrm{~J}\) of heat energy is given off in \(1 \mathrm{sec}\) from a vessel maintained at a temperature gradient of \(30 \mathrm{~km}^{-1}\), the surface area of the vessel is ____________
[Thermal capacity of the vessel \(=\) \(400 \mathrm{Wm}^{-1} \mathrm{~K}^{-1}\) ]
A. \(1.0 \times 10^{3} \mathrm{~m}^{2}\) B. \(1.0 \times 10^{2} \mathrm{~m}^{2}\) C. \(9.0 \times 10^{4} \mathrm{~m}^{2}\) D. \(9.0 \times 10^{2} \mathrm{~m}^{2}\)
