I need help with these two questions from the Jamaica Letter by Simon Bolivar

Describe the technology advancements that lead to explorers being able to sail great distances. [[ps: doesn't explain where. i am only speculating it's in europe.

Chief justice earl warren stated, “separate educational facilities are inherently unequal.” what did the use of “inherently” imply about segregation? 1/ by its very definition, it cannot be equal. 2/ it is an integral part of american society. 3/ based on its meaning, separation is a natural inclination. 4/ it was intended to be a state right, not a national mandate.

Which factor was a major cause of the great depression of the 1930?