Describe the techniques used by Ancient Egyptians and people living in Mesopotamia to meet their water and food needs.

Through Irrigation, Herding, and Agriculture

Explanation:

The harsh climate in Egypt and Mesopotamia provided them with very little rainfall. So, they created an advanced irrigation technology that allow them to distribute waters from major rivers the neighborhood where citizens lived.

As for food, ancient Egypt's and Mesopotamia use similar method as European countries. Through animal farming and Agriculture. Their climate  still enabled several types of grain, fruits and animals to survive. (such as Flax, Goats, pomegranates, etc)

the authority to tax.

the western roman empire flourished, but the eastern portion of the empire struggled.