Final answer:
The function f(x) = 20 is a horizontal line and has a constant value of 20 on 0 ≤ x ≤ 20, which means there are no intervals where f(x) is less than or equal to 0, as it is always positive.
Step-by-step explanation:
To determine the intervals on which f(x) ≤ 0, let's consider the information about the function provided. The graph of f(x) is indicated as a horizontal line, which implies that it has a constant value for all x in the domain. The function f(x) = 20 is a horizontal line and has a constant value of 20 on 0 ≤ x ≤ 20, which means there are no intervals where f(x) is less than or equal to 0, as it is always positive.
Since no specific equation is given for f(x), we can use the information that the function f(x) = 20 is for 0 ≤ x ≤ 20.
Because f(x) is a constant and the value is 20 everywhere on the interval 0 ≤ x ≤ 20, it never dips below 0. Therefore, there are actually no intervals on which f(x) ≤ 0 within the given domain. The function remains positive throughout the interval from x = 0 to x = 20.