What happened to american industry after the civil war?

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.

What was feudalism? (define the structure)

What important discovery was made by edmond halley and alexis clairaut, using newton's ideas of mathematics and gravity? they created the scientific method to outline how science should be conducted. they were able to find the orbit of a comet and predict the year of its return. they discovered the three newest planets--uranus, neptune, and pluto. they explained why objects appear to have color.