Why was the introduction of corn and potatoes to europe and asia so significant

Which of the following was a key accomplishment of the people of songhai? a. they had a strong military and became the largest empire in west africa. b. they established a center of islamic scholarship. c. they worked with iron and prospered from the gold-salt trade. d. they dominated in the trade of ivory, enslaved people, and animal skins.

Earlier studies were more slanted toward a. the upper class. c. caucasian males. b. teenagers in school. d. caucasian females. select the best answer from the choices provided a b c d

Energy is the total kinetic energy of particles of matter.(chose wisely & pick one) a. mechanical b.thermal c.electrical d.chemical