Final answer:
The change in net operating income due to a 250 unit increase in sales volume and a $1,000 total sales increase cannot be accurately estimated without further information on unit costs and selling price.
Step-by-step explanation:
The estimated change in the company's net operating income if it increases sales volume by 250 units and total sales by $1,000 cannot be determined with the information given. To calculate the change in net operating income, we need information about the unit cost and the unit selling price. For instance, if we assume the unit selling price is uniform and equals the increase in total sales ($1,000) divided by the increase in sales volume (250 units), we get a $4 increase per unit. However, without knowing the costs associated with producing the additional units, we cannot determine the impact on the net operating income.