I think the correct answer from the choices listed above is option D. Human height is determined by several genes located on different chromosomes which is an example of a polygenic trait. These traits are being controlled by more than one gene. Hope this answers the question.
The unit for power in electricity should be watt. The power show how many energy transferred during a time and the SI unit would be joule per second.
The bill is charging for the amount of energy. The energy could be calculated by multiplying the power with time. In this case, the power in kilo watt will be multiplied by the duration in hour which make the kilowatt hour.
I think the correct answer from the choices listed above is option A. Directional selection can be distinguished from disruptive selection by the elimination of extreme variations of traits. Directional selection is a natural selection where an extreme phenotype is favored than others.
