Problem: Most of the English colonists had arrived as indentured servants, hiring themselves out as laborers for a fixed period to pay for their passage. In the early years the line between indentured servants and African slaves or laborers was fluid. Some Africans were allowed to earn their freedom before slavery became a lifelong status. Most of the free colored families formed in North Carolina before the Revolution were descended from unions or marriages between free white women and enslaved or free African or African-American men. Because the mothers were free, their children were born free. Many had migrated or were descendants of migrants from colonial Virginia. As the flow of indentured laborers to the colony decreased with improving economic conditions in Great Britain, planters imported more slaves, and the state's legal delineations between free and slave status tightened, effectively hardening the latter into a racial caste. The economy's growth and prosperity was based on slave labor, devoted first to the production of tobacco.
Most English colonists arrived as what?
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Answer: indentured servants

Problem: In general relativity, a vanishing stress-energy tensor implies, through Einstein field equations, the vanishing of all the components of the Ricci tensor. Vacuum does not mean that the curvature of space-time is necessarily flat: the gravitational field can still produce curvature in a vacuum in the form of tidal forces and gravitational waves (technically, these phenomena are the components of the Weyl tensor). The black hole (with zero electric charge) is an elegant example of a region completely "filled" with vacuum, but still showing a strong curvature.
What kind of electric charge does a vanishing stress-energy tensor have?
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Answer: unanswerable

Problem: Doctrinal development has had an important place in the restoration of the Preachers. Several institutions, besides those already mentioned, played important parts. Such is the Biblical school at Jerusalem, open to the religious of the order and to secular clerics, which publishes the Revue Biblique. The faculty of theology at the University of Fribourg, confided to the care of the Dominicans in 1890, is flourishing, and has about 250 students. The Pontificium Collegium Internationale Angelicum, the future Pontifical University of Saint Thomas Aquinas, Angelicum established at Rome in 1908 by Master Hyacinth Cormier, opened its doors to regulars and seculars for the study of the sacred sciences. In addition to the reviews above are the Revue Thomiste, founded by Pere Thomas Coconnier (d. 1908), and the Analecta Ordinis Prdicatorum (1893). Among numerous writers of the order in this period are: Cardinals Thomas Zigliara (d. 1893) and Zephirin Gonzalez (d. 1894), two esteemed philosophers; Alberto Guillelmotti (d. 1893), historian of the Pontifical Navy, and Heinrich Denifle, one of the most famous writers on medieval history (d. 1905).[citation needed]
What school does not publish the Reve Biblique?
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Answer:
unanswerable