This statement is true: <span>The mineral ores for gold and silver are commonly found in the earth's crust.
These two types of metals are known as native metals because they are naturally occurring within the Earth's stratosphere. These metals are usually found through mining processes because they are often found mixed with sediments and other soil components. One method of acquiring gold is called gold panning while silver is obtained mixed with silver sulfide and sulfosalt minerals.</span>
Answer:
B) Nitrogen-fixing bacteria and lightning
Explanation:
Nitrogen cycle is the natural process in which atmospheric nitrogen is converted into nitrite and nitrate with the help of bacteria.
Nitrogen cycle is directly dependent on nitrogen-fixing bacteria and lightning.
As bacteria are responsible for most of the chemical conversion in the nitrogen cycle such as nitrogen fixation (first step) is done by soil bacteria (Cyanobacteria) that form ammonia, which is toxic to plants; nitrification in which ammonia is converted into nitrites and nitrates with the help of Nitrobacter and denitrification bacteria involve Pseudomonas, and Achromobacter which convert nitrite and nitrate into nitrogen.
The lightning breaks nitrogen molecules and allow it to combine with oxygen in atmosphere which further dissolve in rain and form nitrates.
Hence, the nitrogen cycle is most directly dependent upon nitrogen-fixing bacteria and lightning and the correct option is B.
Answer:
I'm sorry but there is no picture above you-
all of the above should be noted for the coroner. because the authorities are trying to solve a homicide.
Answer:
Evolution is the gradual change in the inherited traits of a population over several generations. natural selection is a mechanism where the members of a population best suited to their environment have the best chance of surviving to pass their genes