Figure out how many times you could lay the jump rope end to end from where your standing to the soccer ball and figure how long the jump rope is then multiply the length by how many times you can lay it end to end to reach the soccer ball
It increases genetic diversity by having two.
The answer is the fourth one: Decrease in the fertility of the soil. If you just do crop rotation (harvesting a crop then planting the same type on the same soil) for many years, the soil just loses fertility because of so many of the same plants just using and depleting the fertility from the soil, making the soil less nutritious for the crops.