What did Rome use to improve trade, collect taxes, and pay soldiers?

Most ancient Romans would have paid their taxes in cash, hard currency, coins made out of gold, silver, or bronze.

Explanation:

albany plan of union, 1754. the albany plan of union was a plan to place the british north american colonies under a more centralized government

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."