I am doing a project to see how the increase in cost per 1000 effects the profit

I am doing a project to see how the increase in cost per 1000 effects the profit

However the cost in the table does not increase by a 1000, Please Please help

I need a formula to highlight the cost as it increases per 1000 so I can see the effect on profit.

Not sure if I am on the right track can anyone suggest any other method to do this, maybe
increase cost per 500 or something, or any other method to analyse profit as the cost increases.