The main motivation would be to make money...
Portugal began to explore and many other after them, because of three principles God, Glory, and Gold. God for their faith to spread in the never ending war against Catholics and Protestants. Glory for prestige for being better than your neighbors. Gold for greed and paying the upkeep of your rather large nation and possibly empire.
The First World Empire was England. Its insurmountable navy was one of the reasons it was possible. Its military also strong. Rich undoubtedly.
Answer:
History
Explanation:
The history of the students in relation to their mathematical skills is a potential threat to validity of the experiment.
