The best option for this question is: '<span>It increases the amount of runoff</span>'. Plant life acts as a barrier to the overland flow of water, thereby slowing the flow and allowing increased infiltration of water into the soil. Deforestation and overgrazing are major contributors to erosion, as plants act to bind the soil, and their removal allows the combination of looser soil and increased runoff to move masses of sediment into rivers and lakes. Deforestation will in fact decrease transpiration and percolation and precipitation rather than increase them.
YY and Yy would result in a plant with yellow seeds. This is because Y is dominant and yellow seeds would show with a dominant homozygous and a heterozygous. It can't be yy because that would be homozygous recessive
If you cut a flatworm in half, both halves can grow into a new individual by fission.