Assuming Newtons law of cooling: (T - TAmb)/(Ti - Tamb) = e-kt This allows the left hand side to decay from 1 to 0. The equation follows from the rate of heat flow being proportional to the difference in temperature between the turkey and the room. (amb = ambient, i = initial)
a) You can solve for k given all the other data. Then you solve for T, knowing k
b) You solve for t given all the other data.
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