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#### Question

A metal ball cools from 64 ^{°}C to 50 ^{°}C in 10 minutes and to 42 ^{°}C in next 10 minutes. The ratio of rates of fall of temperature during the two intervals is _______.

(A) `4/7`

(B) `7/4`

(C) 2

(D) 2.5

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