Answer:
The correct option is A. they evolved from land mammals.
Explanation:
Evolution can be described as a process through which organisms in a species change over a period of time due to the natural selection of the environment. Those organisms that have many similarities in their functions or structures are considered closer to one another and have the same common ancestors.
The properties mentioned in the question about cetaceans resembles the properties of land mammals. For example, cetaceans lack gills and breathe air. Land mammals also do not have gills and need to respire for living. The cetaceans have fin bones which are similar to the limb bones in the land mammals. Hence, these observations show that cetaceas have evolved from land mammals.
Answer:
C. in areas with different air pressures
Explanation:
"Convection currents occur within:
The geosphere – plate tectonics
The atmosphere - wind
The hydrosphere - ocean currents"
Hope this helps u.
Answer:
Probably B
Explanation:
They all explain it, honestly, but B sounds the least like an answer they would accept as true. It's also kind of sus that they have 2 different answers about reacting differently to stress, and B is definitely the least likely of the two to be correct. Sorry I couldn't be more helpful, I'm only here because I searched for the answer myself. Good luck.
The correct answer is outer electrons. These are sometimes called 'valence electrons', and they are responsible for the element's properties and how it forms bonds. For example, elements in Column 2 are likely to form ionic bonds with elements in Column 16. This is because elements in Column 2 have 2 outer electrons, while elements in Column 16 have 6 outer electrons. If the element in Column 2 gives its 2 electrons to the element in Column 16, then the former will be stable because the energy level underneath will be complete, and the latter will be stable because it will have a complete outer energy level with 8 electrons.
Hope this helps!
