He studied the fossils' age and how tall the mountains are. He also studied how old they are. I don't know about Coal Beds but he also used balloons to find out the continents were once a big supercontinent called Pangaea and they apparantly drifted apart
Answer:Portugal
Explanation:In 1492 Columbus discovered the New World of the Americas. Portugal and Spain became the early leaders in the Age of Exploration. Through the Treaty of Tordesillas the two countries agreed to divide up the New World
Answer:
Checks and balances system I'm pretty sure.
Explanation:
Explanation:
The development of such major Sudanic kingdoms and empires as Ghana, Mali, Songhai, the Hausa states, and Kanem-Bornu along the southern fringes of the Sahara had a number of important consequences for the history of western Africa as a whole
