Answer:
(a)-Rills, and arroyos or gullies develop mainly during prolonged droughts.
Explanation:
Soil erosion is the process of erosion, transport and sedimentation of soil, subsoils and rocks as an effect of the action of erosive agents such as water, winds and living things. The process of disintegration of rock particles (called sediments) is caused by the action of weathering (a set of chemical, physical and biological processes that cause soil and rock wear).
About soil erosion, we can confirm that the following information is true:
- Grasses and other vegetation, windbreaks, and contour cropping will help reduce soil loss from cultivated lands.
- Soils form naturally by weathering; if protected from erosion, sound management can maintain or enhance their nutrient levels and textural characteristics.
The phenotype is - 75 % red and 25 %brown.
The genotype is hRhR - 25%
hBkhR - 50%
hBrhBk - 25%.
<h3><u>Explanation:</u></h3>
The cross given here is a simple dominant - recessive relationship between the three types of alleles of hair colour. The genes of this characteristics are present in autosomes, so will be segregated equally among all the sexes of the offsprings.
Now the genotype of auburn and red with black mother is given. So during gametogenesis, the gametes from the parents will be
Father - hBr and hR
Mother - hBk and hR
So, the probable combinations are hBrhBk, hBrhR and hBkhR.
The frequency of the combinations are 25%, 25% and 50% respectively.
The phenotypic ratio will be red : brown as 3:1.
75% is my answer! I hope you get it right!