Light with an average flux of $20 \, W/cm^2$ falls on a non-reflecting surface at normal incidence having a surface area of $20 \, cm^2$. The energy received by the surface during a time span of $1 \, minute$ is $............ \, J$.
- A$48 \times 10^3$
- B$10 \times 10^3$
- C$12 \times 10^3$
- D$24 \times 10^3$
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