Final answer:
Exponential regression is the tool used to determine an exponential function from two points.
Step-by-step explanation:
The tool used to determine an exponential function from two points is Exponential regression (option b).
Exponential regression is a statistical method used to model the relationship between two variables when the data exhibits exponential growth or decay. It can be used to create an equation that represents the exponential function that best fits the given data points.
For example, if we have two points (x1, y1) and (x2, y2), exponential regression can help us find the equation of an exponential function of the form y = ab^x where a and b are constants. By fitting the data to this equation, we can determine the values of a and b that best represent the relationship between the variables.