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Heat lost by copper = heat gained by water
mcCc?? =mwCw??
4 x 400 (91- 21) = mw x 4200 x (21-20)
(4 x 400 x 70)/4200 = mw
26.7 kg= mw
joseph rimiru answered the question on October 11, 2017 at 17:24
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