Firms use marginal analysis to determine production output levels by

 Studying the effect on revenue of small changes to the number of items produced.

Hope that helps!!

the ones that are losing there jobs

2686-2181 bce-- "egyptian civilization developed along the nile river in large part because the river’s annual flooding ensured reliable, rich soil for growing crops."

1069-664 bce-- "ancient egyptians developed wide-reaching trade networks along the nile, in the red sea, and in the near east."