The answer is D, 15,000 x 0.2= 3000 add that together =18,000
<span>Human skin color variations are primarily being determined by the type and amount of melanin pigment which is the skin.
The reason is the amount of melanin present, pigment present which determines the color of skin the more the melanin the more dark color they are.
Human skin color variation is likely evolved in response to differences in intensity of sunlight around the world. Reason being it has been developed because of different exposure of humans to the varied environment during migration. Human skin color variation evolved recently in hominid evolution.</span>
False, our beliefs and opinions on politics and economics are unrelated to the environment.
Answer:
keystone species
Explanation:
Keystone species are indispensable species that are essential to the maintaining of the balance of an ecosystem, and also play a major role in the way species in the ecosystem interrelate. The absence or removal of a keystone species from a habitat or ecosystem would lead to the disruption and imbalance of the ecosystem, and as such lead to the extinction of other species.
An example of a keystone species is the bee. Bees are very important in pollination of flowering plants and also ensure their survival. This plants serve as home to various insects that are source of food to birds. The removal of bees from this ecosystem would affect the ecological balance of this ecosystem.