What is the idea behind a "single-payer" system of health insurance?

How was slavery in mesoamerica, africa, and the arab world similar? many enslaved people were forced to pledge loyalty to their owners. many enslaved people worked in exchange for protection from foreigners. many enslaved people were captured during war. many enslaved people taught and tutored children.

The north was victorious in the battle of bull run true or false

What is the relation between the hover dam and the gold rush