Final answer:
Without specific temperature data or a cooling rate, we cannot perform a regression analysis to predict when Selena's pizza will cool to serving temperature. Selena would need to monitor the pizza's temperature and serve it once it hits 68°F.
Step-by-step explanation:
To determine when Selena can serve the pizza that has cooled to room temperature (68°F), one would typically collect temperature data over time and perform a regression analysis to predict when the pizza will reach the desired temperature. However, since the question does not provide any temperature data points or a specific cooling rate, we cannot complete a regression without additional information.
In a practical setting, Selena might use a thermometer to check the pizza's temperature at intervals and record the time versus temperature. These data points could then be used to create a regression model, such as a linear or exponential decay model, depending on the cooling characteristics of the pizza. With the regression model, she could predict when the temperature will hit 68°F and be ready to serve.
Without concrete data and a regression analysis, we can only advise Selena to monitor the pizza's temperature and serve it once it reaches 68°F.