Select the correct answer from each drop-down menu. Michael is giving a presentation on the ecological pyramid of numbers. Help him complete the sentences.
In the pyramid of numbers generally, the
are the highest in number. Therefore, they occupy the base of the pyramid.
The subsequent trophic levels where the numbers of organisms decrease occupy the upper levels. However, pyramid of numbers does
not prove useful in most of the cases. Scientists have to
the number of organisms in each trophic level, which is a difficult
task.

Why is earth's outer core hotter than earth’s oceanic crust? earth’s oceanic crust is denser than earth’s outer core is. earth’s oceanic crust has lava flowing from the mantle. earth’s outer core has a composition of solid iron and nickel. earth’s outer core is deeper within earth than oceanic crust is.

Astudy by solloch and et. al., in 2017, gives the map above which shows the frequency of alleles with a ccr5-delta32 mutations over 87 different countries. this mutation deletes the presence of a co-receptor (ccr5) on the outside of human t-cells (lymphocytes). some viruses, such as the one responsible for the black death and human immunodeficiency virus (hiv), require this receptor for attachment to host cells during the infection process. the black death was an epidemic that passed over northern europe during the 14th century killing nearly 60% of europeans. according to this information, which explanation best explains why northern europeans show a greater immunity for hiv than some other parts of the world?

Kudzu vines grow by climbing and wrapping around trees. trees covered by kudzu can die because they are starved of sunlight. what type of relationship exists between the trees and the kudzu growing on them?