A black body calorimeter filled with hot water cools from 60 degrees celsius to 50 degrees celsius in 4 min and from 40 degrees celsius in 8 min. The approximate temperature of surrounding is
a) 10 degrees celsius
b) 15 degrees celsius
c) 20 degrees celsius
d) 25 degrees celsius
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https://www.meritnation.com/ask-answer/question/a-body-cools-down-from-80c-to-60c-in-10-minutes-when-the-tem/thermal-properties-of-matter/3669150