Answer:
D: All real numbers or (-∞, ∞)
R: (-∞, 2] or y ≤ 2
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Domain:
The graphed function has arrows on both ends, meaning that it will extend to -∞ and ∞. Therefore the Domain is:
D: All real numbers or (-∞, ∞)
Range:
The graph extends downward infinitely, so the graph will extend to y = -∞ as x ⇒ -∞ and x⇒ ∞.
The graphed function has a maximum, or greatest y-value at y = 2, therefore:
R: (-∞, 2] or y ≤ 2