What was the spoils system

How did german physicist werner heisenberg's uncertainty principle shake beliefs in newtonian physics?

What was true about sharecropping? a. landowner provided free tools and seeds. b. workers could leave the land if they failed to make money. c. landowners often took advantage of workers. d. workers received ownership of the land they farmed after a set number of years.

Did the spanish settlers and missions have a positive effect on world history? why, what did they do that was positive? why was the treaty of paris (1763) good for the world/world history? did the plymouth colony have a positive effect on world history? why, what did they do that was positive?