Answer:
Step-by-step explanation:
From the picture attached,
Graph (A)
Domain of the function : (-∞, ∞) or a set of real numbers
Range of the function : (-∞, ∞) or a set of real numbers
Graph (B),
Domain : (-∞, ∞) Or a set of real numbers
Range : (-∞, 6] Or x ≤ 6
Graph (C),
Domain : [-2, ∞) or x ≥ -2
Range : (-∞, ∞) Or a set of real numbers
Therefore, Graphs (A), (B) have the domain of all real numbers and Graph (C) has the range of all real numbers.
Since all the parabolas are not the functions,
Therefore, Graph (C) is not a function. Graphs (A) and (B) are the functions.
Just square the top and bottom of the fraction. 
and 
so we have 12/16 and then we reduce to 3/4