Final answer:
The relationship between 15, 16, 17, and 18 is neither linear nor exponential.
Step-by-step explanation:
The relationship between 15, 16, 17, and 18 is neither linear nor exponential. A linear relationship is one where the values increase or decrease at a constant rate. An exponential relationship is one where the values increase or decrease exponentially. In this case, the values 15, 16, 17, and 18 do not follow a clear pattern of linear or exponential growth. They are simply four consecutive numbers.