Which statement correctly describes one of Aryabhata’s contributions to the sciences? He discovered how eclipses work.
He created vaccines to prevent diseases.
He created new surgical procedures.
He discovered new chemical reactions.

According to douglass, what does the singing of a slave communicate? how does douglass feel about slave songs? in what way is slaves singing misinterpreted by some people? .

How does nafta affect relations between the united states and canada? a. it bans immigration between the two countries. b. it opens the borders between the two countries. c. it raises taxes on trade between the two countries. d. it allows free trade between the two countries.

The mongols were descendants of a. pastoral nomadic tribes b. tibetan tribes c. shang nobility