Who was the last communist leader of the soviet union before it collapsed?
a) boris yeltsin
b) mikhail gorbachev
c) vladimir putin
d) joseph stalin

before, mexicans where an indian tribe but when the spanish took over, they changed their language to spanish.

hope this : d

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.