A black body radiates at the rate of $W$ watts at a temperature $T$ . If the temperature of the body is reduced to $T/3$ , it will radiate at the rate of (in Watts)
  • A$\frac{W}{{81}}$
  • B$\frac{W}{{27}}$
  • C$\frac{W}{9}$
  • D$\frac{W}{3}$
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