a) hunter gatherers who built mounds
The various cultures collectively termed "Mound Builders" were inhabitants of North America who, during a circa 5,000-year period, constructed various styles of earthen mounds for religious, ceremonial, burial, and elite residential purposes.
NIxon helped because he wanted to be nice.
Barriers and road markings are there to protect vulnerable road users by separating the <u>lanes </u>used by road users.
Vulnerable road users include:
- Pedestrians
- Motorcyclists
- Cyclists
Barriers and road markings separate the lanes used by motorists in cars and those used by these vulnerable road users to ensure that the motorists don't injure them.
In conclusion, the lanes are separated to protect vulnerable road users.
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