You have ten workers who are all equally skilled and who can do each other worker's job with the same efficiency. The first worker does a task worth $100, the second, $90, and so on
until the last whose task is worth $10. Worker number one comes to you, demands a raise,
and threatens to quit if the raise is not forth coming. How much at most should you be
willing to pay worker number one?

It really depends. If all jobs are similar and demand the same requirements, I would find a middle amount like $25 for all ten workers.

the u.s. census bureau produces data on the population and economy nationwide. it can you to analyze the kind of people living in your neighborhood. it does not show you the market of people willing to buy your product or an existing market for your product. that will require more market research. the census bureau only gives you an insight to the demographics in your area.