Which event happened last? a. president roosevelt proposed the lend-lease act b. germany begins invading other countries. c. the japanese attacked the military base at pearl harbor , hawaii d. japan invades china

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.

answer; ///i do believe that the correct answer is (d); ///athens had a small population;