Correct answer: B.
We know that s<span>ome populations have a high frequency of the mutant allele, which indicates that there was already a wide spreading of it so that when the disease attacked the population, cause the necessary selection to promote the high frequency of the mutant allele. If the mutant allele appeared only when the disease struck, the mutant allele frequency wouldn't be high because this is a process that takes time.</span>
We can't be sure that A. is true, we'd need more information as to whether there is any advantage in having at least one allele. We do know that it is a recessive allele, therefore, most likely, there isn't any advantage.
C. - we can't foresee whether the disease would come to a closure. The virus could evolve alongside with the selection and this mutated allele would not be of any use.
There is only a genetic advantage - D. - in being heterozygous if there is an advantage having only one mutated allele, which we don't know.
Answer: All ecosystems modified or created by man specifically to grow or raise biological products for human consumption or use. This includes cropland, pasture, orchards, groves, vineyards, nurseries, ornamental horticultural areas, and confined feeding areas.
The answer is C. The first option is highly unlikely, the second option is impossible, and C is a much more likely answer than D.
Because: Some of the work done by the machine is used to overcome the friction created by the use of the machine. ... Work output can never be greater than work input. Machines allow force to be applied over a greater distance, which means that less force will be needed for the same amount of work.
Hope this helps!
Answer:
Trees are important because the provide the paper we need to make money. Trees are apart of plants,and plants provide oxygen for humans to breathe.
Explanation:
Hope this helps!