What did Isaac Newton discover/create/study while quarantining from the
Black Plague?

Discovery of Calculus

Explanation:

In 1665, he discovered the generalised binomial theorem and began to develop a mathematical theory that later became infinitesimal calculus. Soon after Newton had obtained his degree in August 1665, the University closed down as a precaution against the Great Plague of London.

crop rotation kepy different plants in the soil instead of once constintly. when switching out plants you have different nutrients being absorbed at different speeds and different roots growing differently therfore the spoil and water flow have to adapt and carry fresh nutrients to carry the constant changes that were going on in the soil.

the answer is a. laws were enacted in the aftermath of the plot to make it harder to free slaves,increasing sectionalism