Try this solution:
D(f): √(2-x)≥0; ⇔ 2-x≥0; ⇔ x≤2 or x∈(-∞; 2].
To do this all you would have to do is (divide 8 into 72 then you would end up to get your mixed number, which is 8 7/8)
Your Welcome! (:
The answer is D because A and B mean the exact same thing and if A and B are graphed the result is C so the only logical answer left is D