A liquid of mass $250 \mathrm{g}$ is kept warm in a vessel using an electric heater. The liquid is maintained at $57 °\mathrm{C}$ when the power supplied by the heater is $30 \mathrm{W}$ and surrounding temperature is $27 °\mathrm{C}$. As the heater is switched off, it took $10 \mathrm{s}$ time for the temperature of the liquid to fall from $47 °\mathrm{C}$ to $46.9 °\mathrm{C}$. The specific heat capacity of the liquid is

• Correct answer
  A

  $8000 \mathrm{J} {\mathrm{kg}}^{-1} {\mathrm{K}}^{-1}$
• B

  $9000 \mathrm{J} {\mathrm{kg}}^{-1} {\mathrm{K}}^{-1}$
• C

  $6000 \mathrm{J} {\mathrm{kg}}^{-1} {\mathrm{K}}^{-1}$
• D

  $12000 \mathrm{J} {\mathrm{kg}}^{-1} {\mathrm{K}}^{-1}$

Hence, the correct answer is option: 'A'.