Genetic changes within and among populations
Answer:
Personally, I believe the information helps.
Explanation:
Without this information the virus would not be contained, we would not have done research, taken samples, tested out the virus, or even attempted to contain it. With this information we can attempt to prevent a break out of the disease again. This is my personal opinion though.
The right option is; d. Runoff describes water movement and infiltration describes water storage.
Runoff is the portion of precipitation, irrigation or snow melt that flows over land as surface water instead of infiltrating or evaporating. Factors that influence runoff are permeability, amount of rainfall, slope and vegetation.
Infiltration is the process by which water or precipitation on the ground surface moves into the soil. Factors that determine the rate of infiltration include; soil type, topography of the land, amount of precipitation, vegetation, and pre-saturation levels.
Metagenomics is the study of genetic material recovered directly from environmental sample. Its field has been responsible for substantial advances in microbial ecology, evolution, and diversity over the past 5 to 10 years and many research laboratories are actively engaged in it now. Using metagenomics, the distinctions between bacterial species are based upon the comparison of DNA nucleotide sequences of different bacterial species.
The resistance of a given object depends primarily on two factors: What material it is made of, and its shape. For a given material, the resistance is inversely proportional to the cross-sectional area; for example, a thick copper wire has lower resistance than an otherwise-identical thin copper wire. Also, for a given material, the resistance is proportional to the length; for example, a long copper wire has higher resistance than an otherwise-identical short copper wire. The resistance R and conductance G of a conductor of uniform cross section, therefore, can be computed as
<span />
where is the length of the conductor, measured in metres [m], A is the cross-sectional area of the conductor measured in square metres [m²], σ (sigma) is the electrical conductivity measured in siemens per meter (S·m−1), and ρ (rho) is the electrical resistivity (also called specific electrical resistance) of the material, measured in ohm-metres (Ω·m). The resistivity and conductivity are proportionality constants, and therefore depend only on the material the wire is made of, not the geometry of the wire. Resistivity and conductivity are reciprocals: . Resistivity is a measure of the material's ability to oppose electric current.
This formula is not exact, as it assumes the current density is totally uniform in the conductor, which is not always true in practical situations. However, this formula still provides a good approximation for long thin conductors such as wires.
Another situation for which this formula is not exact is with alternating current (AC), because the skin effect inhibits current flow near the center of the conductor. For this reason, the geometrical cross-section is different from the effective cross-section in which current actually flows, so resistance is higher than expected. Similarly, if two conductors near each other carry AC current, their resistances increase due to the proximity effect. At commercial power frequency, these effects are significant for large conductors carrying large currents, such as busbars in an electrical substation,[3] or large power cables carrying more than a few hundred amperes.
