The true statement about the graph's slope is (c) Its slope is zero.
<h3>How to determine the true statement?</h3>
From the question, we have:
A horizontal line is at y = 2.5.
The horizontal line implies that the cost of lunch do not change
Horizontal lines have a slope of 0
Hence, the true statement about the graph's slope is (c) Its slope is zero.
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