Quenching is the process of immersing a hot metal object in a bath for a specified time to obtain certain properties (such as hardness). A copper sphere 25 mm in diameter, initially at 300C, is immersed in a bath at 0C. The following are the measured data of temperature vs. time. Find a functional description of these data. Plot the function and the data on the same plot.

Time (s) 0 1 2 3 4 5 6

Temp C 300 150 75 35 12 5 2