Which of these inventions most improved the ability of americans to communicate across the country?

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.

What is the name of this mountain range found in northern africa?

On this map which states would the tropic of cancer run through