The kingdoms of ghana, mali, and songhai were all able to achieve golden ages in part because of their
(1)reliance on sugar plantations in the niger delta
(2)control of trans-saharan trade routes
(3)discovery of oil reserves in the gulf of guinea
(4)ability to use the natural harbors on the atlantic ocean coast

Which of the following was used only once, to ratify the 21st amendment (repealing prohibition)? a.three-fourths of both houses of congress. b.three-fourths of the state legislature approved it. c.two-thirds of the state legislature approved it. d.ratifying conventions in three-fourths of the states approve it.

How did the completion of the transcontinental railroad change the lives of american citizens? a-it increased the wealth of all americans and enabled them to travel more.b-it made cross-country travel too expensive for ordinary americans.c-it decreased the safety of americans who moved to settle the plains.d-it shortened travel time between the east and west for all americans.

What is the main social system that existed in ancient china?