In a room where the temperature is ${30^o}C$, a body cools from ${61^o}C$ to ${59^o}C$ in $4$ minutes. The time (in min.) taken by the body to cool from ${51^0}C$ to ${49^0}C$ will be ....... $\min$
  • A$4$
  • B$6$
  • C$5$
  • D$8$
Medium
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