Answer:
Ian is correct
Explanation:
The range of a function is the set of all possible values that the function can take. In other words, it is the values of y lying between minimum and maximum
From the graph we can see that the minimum value of y = 0
Maximum value of y = 30
So the range is 0 ≤ y ≤ 30
So Ian is correct
(Note that y ≤ 30 can include negative values which is not possible in this case)