Answer:
$24 = $0.40(60)
Explanation:
Match the input value and its location in the equation.
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$24 = $0.40(60)
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Additional comment
When input is liters and output is dollars, the constant of proportionality must have units of "dollars per liter." The dollar sign of these units is not shown in the left panel, but is shown on the answer choices. If you understand units conversion, this should not be a mystery. (The mystery is why the curriculum materials are inconsistent.)