16 would be the range. The lowest value is 5, and the highest value is 21. You just subtract those two which gives you 16! (:
Answer:
Step-by-step explanation:
What's the question or what you are trying to find
Answer: They are inverses of each other
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Explanation:
We'll need to compute h(f(x)) and f(h(x)) to see if we get x each time.

and,

Both composite functions lead to x each time.
The equations h(f(x)) = x and f(h(x)) = x being true means each function is the inverse of the other.