This is a good discussion question for your own classes. At each time, t, the measured temperature, T, is a specific number measured by the TI-CBL and temperature probe. Thus, the measured temperature is determined by the time. This gives us a function

In the United States the temperature, T, is commonly measured in degrees Fahrenheit but elsewhere degrees Celsius are more common. The time, t, might be measured in hours or minutes.

This function most likely cannot be expressed by a simple algebraic formula. In fact, the only way to determine this function is by measurement. Students often confuse functions with formulas. Some functions can be expressed by formulas but most functions are not so simple.