Final answer:
The interval where f(x) > 0 is 0 ≤ x ≤ 20.
Step-by-step explanation:
To determine the interval where f(x) > 0, we need to examine the graph of the function f(x). Since the graph of f(x) is a horizontal line and 0 ≤ x ≤ 20, we know that f(x) is positive for all values of x within that range. Therefore, the interval where f(x) > 0 is 0 ≤ x ≤ 20.