Why would resources of water and flint have been important to early humans?

I think water and flint would have been important to early humans because water is one of the basic needs of a species, and water can have a variety of uses, like cleansing themselves, hydrating themselves, and putting out various fires started by lightning, themselves, and the sun. Flint would be also very useful to early humans because this would have enabled them to start fires, cook food, make sharper and more accurate arrows and tools. In conclusion, I think water and flint would have been very useful to early humans.

Explanation: ik its kinda short but im kinda hungry so imma eat dinner  

b) the confederacy had to pay all union war expenses.

the constitution gives congress the power to regulate commerce "among" the several states.