Final answer:
The domain of the function is [0, 20] and the range is {-5}.
Step-by-step explanation:
The domain of a function is the set of all possible input values, or x-values, for which the function is defined. In this case, the function is defined for 0 ≤ x ≤ 20, so the domain is the interval [0, 20].
The range of a function is the set of all possible output values, or y-values, that the function can produce. Since the graph of the function is a horizontal line, the y-value remains constant at -5. Therefore, the range is {-5}.