A cup of coffee cools from $90^{\circ} \mathrm{C}$ to $80^{\circ} \mathrm{C}$ in $\mathrm{t}$ minutes, when the room temperature is $20^{\circ} \mathrm{C}$. The time taken by a similar cup of coffee to cool from $80^{\circ} \mathrm{C}$ to $60^{\circ} \mathrm{C}$ at a room temperature same at $20^{\circ} \mathrm{C}$ is :
  • A$\frac{13}{10} \mathrm{t}$
  • B$\frac{13}{5} \mathrm{t}$
  • C$\frac{10}{13} \mathrm{t}$
  • D$\frac{5}{13} \mathrm{t}$
NEET 2021, Medium
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