1. In a soil profile, the depth of the different layers may vary widely and some layers may be missing altogether
2. In a fine textured soil, sand is predominant
3. Farmers used the term heavy soil for the clayey or fine textured soil.
4. In a Massive Soil Structure, water flow is rapid.
5. In the process of infiltration, the water seeps into the soil and the color of the soil
becomes lighter as it is wetted.
6. The soil has low infiltration rate when it seeps water at the rate of less than 15mm
hour.
7. Soil Texture influences the infiltration rate of soil
8. The capillary rise of a coarse textured soil reaches up to 80 cm.
9. Soil erosion by water depends on the rate of flow of surface runoff water.
10. In a Prismatic Soil Structure, water flow is rapid.
11. Contour lines are useful means to illustrate the topography of a field on a flat map.
12. A bench mark is a permanent mark established in a field to use as a reference
point
13. The depth of the groundwater table varies greatly from place to place, mainly due​

Over the past 60 years, many amphibian species have experienced significant population declines and some species have become extinct. scientists suspected that local human activities such as the destruction of wetlands, regional pollution, and deforestation were the main reasons for these losses. however, research over the past 20 years reveals significant amphibian population declines in protected areas of the world, such as nature preserves and parks. these global declines suggest widespread problems including increased ultraviolet radiation, acid rain, and disease. in switzerland, for example, 14 of the 20 native amphibian species are threatened with extinction. chytridiomycosis is a fungal disease first identified in 1998 as a cause of massive amphibian deaths. in some severely impacted populations, a few individuals have survived, perhaps because of some natural resistance. if these resistant individuals continue to survive and prosper, new resistant populations might emerge. this would be an example of the founder effect artificial selection genetic drift natural selection sexual selection

Monitor and apply fix up strategies

Two students are working together on an experiment that measures the effect of different liquid fertilizers on the thickness of plants’ stems. which is most likely to result in the greatest amount of error in their scientific experiment? a.one student measures the plant stem widths by using calipers. the other student measures the widths of the same plant stems again by using a different pair of calipers. b.one student measures the plant stem widths by using calipers. the other student types the measurements as they are taken into a computer spreadsheet. c.one student weighs liquids for the experiment by using a calibrated scale. the other student weighs liquids for the experiment by using a different calibrated scale.