a. The y-intercept of the trend line represents that Devonte earns $7.00 per hour when he serves 0 customers.
b. Devonte's hourly earnings increase for each additional customer that he serves is $2.50.
Part A: The y-intercept of the trend line represents that Devonte earns $7.00 per hour when he serves 0 customers. This is because the y-intercept represents the point where the trend line crosses the y-axis, which corresponds to a value of x = 0. In this case, when x = 0, the equation of the trend line gives us y = 7.00.
Part B: According to the equation of the trend line, Devonte's hourly earnings will increase by $2.50 for each additional customer that he serves. This is because the slope of the trend line represents the change in y (hourly earnings) for each unit change in x (number of customers served). In this case, the slope is 2.50, which means that Devonte's hourly earnings will increase by $2.50 for each additional customer he serves.