Final answer:
The situation describes a quantitative functional relationship with a domain for the function ranging from 0 to 3 pounds of candy, inclusive of any fraction within this interval.
Step-by-step explanation:
When Kenny buys candy at a corner store for $4.50 per pound and he can buy at most 3 pounds, the type of data represented in this situation is quantitative, as it deals with numerical values that can be measured and quantified. Specifically, this is a functional relationship between the weight of candy purchased and the total cost.
The domain of a function is the set of all possible input values. In this scenario, the domain would be the number of pounds of candy that can be purchased which ranges from 0 to 3, including any possible fraction within that range since candy can typically be bought in fractions of a pound. Therefore, the domain of Kenny's candy purchase function is [0, 3].