Definite article is used before a noun (person place or thing) to indicate that the identity of the noun is known to the reader.
indefinite article is used before a noun that is general or when its identity is not known.
<span>George Simmel was a pioneer in sociological studies due to the fact that he developed the concept of the sociological imagination, and believed that societies can be understood through an empirical scientific approach known as positivism which is still used in research today.</span>
Answer:
Instead of a brain, echinoderms have a ring of nerves located around their mouth area that governs their nervous responses. This ring coordinates their motion, their eating, basically anything that requires nerve control.
Explanation:
