In an exponential function, which part of the expression holds the variable?

1. An exponential function looks different from the ones met earlier. 2. The variable has moved to a new position in the expression. 3. In this function, the variable is the exponent. 4. So the answer is the exponent. _Source: OpenStax Intermediate Algebra 2e (CC BY 4.0), Ch 10, sections 10.1-10.2 'Evaluate and Graph Exponential Functions'_