It is given that, Mass (m) = 5.00kg

Temperature (ΔT) = 80.0 K

Heat supplied (Q)= 1676 KJ= 16,76,000 J

Specific heat can be calculated by the formula,

C = \frac{Q}{m \Delta T}

Substituting the known values in the above formula, we get,

C = \frac{16,76,000 J}{(5kg)(80 K)}

C = 4190 J kg-1 K -1

Hence, the specific heat of water is 4190 J kg-1 K -1 .

I found an answer from ntrs.nasa.gov

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broad heat transfer data base to determine where it could appropriately be used for hrat ... (5) The hot water loop: heated the preplate and recovery walls, using ...

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Will cold water boil faster than hot water? - Quora

You need to add a lot of energy to liquid water in order to boil it. ... Um, call me dumb but I don't see how, all else being equal, cold water could ever ... when heat energy is added to a substance, the temperature will change by a certain amount. ... of the pot, the environment conditions, rate of heat transfer, the method of heat ...

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