Answer 1) A) Weathered rock and decomposed organic remains
Explanation : Observing an handful of soil would most probably have the weathered particles of the rock which are found in tiny small size and also it would have humus in it which is decomposed organic matter found in the soil.
Answer 2) B) Use more land to plant crops
Explanation : To decrease erosion of the Earth's surface one needs to hold the soil this can be achieved by planting more plants on that land. This will increase the ability of the roots of the plant to hold more soil in the form of nutrients.
Answer 3) D) Top Soil and Organic matter
Explanation : The soil profile includes the uppermost horizon as the top soil, it is considered as the horizon O while the lower horizon C is mostly composed of the organic matter which helps the soil to maintain its fertility.
Answer 4) C) They decompose the remains of plants and animals and add nutrients back to the soil.
Explanation : The main function of the micro-organisms is to decompose the dead and decaying matter. It increases the soil fertility by decomposing the organic matter and adds nutrients to the soil.
Answer 5) C) Physical Weathering
Explanation : Physical weathering is a phenomena which occurs in the rocks due to uneven surrounding temperatures which results into cracking and breaking down of the rocks to form sediments.
Answer 6) D) The plates that formed these mountains were once under an ocean.
Explanation : Fossils are dead imprints remains of the extinct species. According to the given information, it is clear that the plates which formed the mountains used to be under the ocean as it contains the dead imprints on its rock.
Answer 7) B) The water from her gutter pipe was washing away the soil in her flowerbed.
Explanation : The problem was soil erosion which was solved by using rocks under the flowerbed. This increased the water retention capacity of the soil.
Answer 8) A) Erosion
Explanation : Clear cut logging is cutting down of the trees in a particular area which would result in soil erosion as there will be no trees to hold the soil and water.
Answer 9) B) Area A was completely underwater in the past.
Explanation : As fossils are found on the rocks of the coasting United States this is a clear indication that the area A was once used to be completely under water. (Submerged in water).
Answer 10) B) Soil 2
Explanation : For growing tomato plant Alexa can use Soil #2 because, it has lots of organic matter in it which will add nutrients to the soil and has clay in it, which gives favorable condition to grow tomatoes.
Answer 11) B) Loam
Explanation : Loam soil is a mixture of soil that is widely used as ideal plant-growing soil. It's a combination soil, containing equal parts of clay, silt, and sand. This helps the plant roots to grow down easily through sand and slit and reach the nutrients of soil.
Answer 12) D) Sediment
Explanation : Weathering contributes to the composition of the soil because it breaks and cracks the rocks into small tiny particles which becomes soil after disintegration.
