Answer:
C. Varieties of an element that differ only in the number of neutrons are called isotopes.
Explanation:
The Earth is approximately 
old. The solar system formed from giant gas clouds which was a part of the solar nebula.
The surface of soil which demarcates two soils of different geological ages is called a unconformity.
Palesol is the soil that lies between sediments or volcanic deposits. If the paleosol is older they have lithified rock.
Hence, option C is true.
The first state was Delaware
In general, animals are perceived by scientists as being relatively intelligent possess by scientist.
Animals are then broken down into two sorts: vertebrates and invertebrates. Animals with a spine are vertebrates. Vertebrates belong to the phylum referred to as Phylum Chordata. Vertebrates are similarly broken down into five instructions: amphibians, birds, fish, mammals, and reptiles.
We can define animal intelligence as the combination of talents and abilities that allow animals to stay in and adapt to their unique environments. What does this actually imply? Animals possess the potential to conform to their surroundings via gaining knowledge of to exchange their habits and behaviors.
Learn more about a general animal here:brainly.com/question/25897306
#SPJ4
