Genetic engineering is the answer
Polygenic is a<span> </span>trait<span> that is controlled by a group of </span>nonallelic <span>genes. </span>For example, humans can be many different sizes. Height is a polygenic trait, controlled by at least three genes with six alleles. If you are dominant for all of the alleles for height, then you will be very tall. ... Skin color is also a polygenic trait, as are hair and eye color. A trait that is controlled by a group of nonallelic <span>genes
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Given that,
The speed of a wave, v = 200 m/s
Wavelength, 
We need to find the frequency of this wave. The relation between wavelength, frequency and the speed is given by :

So, the frequency of this wave is 100 Hz.
DNA can illustrate that evolution has occurred since in the process of natural selection advantegeous genes or traits have been selected to pass on through generations and further more evolve as long as the species survies and is successful in reproducing.