Final answer:
The constant of proportionality between the total amount earned by the credit card machine fees and the dollars earned by the bodega is 3.
Step-by-step explanation:
The question asks about the constant of proportionality between the total amount earned by credit card machine fees and the dollars earned by the bodega. In this question, we are asked to identify the constant of proportionality between the total amount earned by the credit card machine fees and the dollars earned by the bodega. The constant of proportionality represents the rate at which the bodega earns money from the credit card machine fees.
From the given options, the correct constant of proportionality is 3. This means that for every dollar earned by the credit card machine fees, the bodega earns $3.