During the "dark ages", as named by historians, why did bridge engineering come to a halt?

Sparta faces threats from without and within the city-state who posed these threats.

The venn diagram below shows some services provided by state and local governments. the answer choices are (1) - creating a police force, (2) - regulating taxicabs, (3) - regulating savings banks, (4) - issuing driver licenses.

What is a characteristic of hunter-gatherer societies?