3. a) Some nouns from the article are missing from the definitions below. How many can you find without looking back at the article?2)1) population (n.) [U] - all the people who live in one area, city orcountryn.) [U] - a process of making water, air, soil, etc.dirty.3)(n.) [U; C] - when sb or sth becomes impossibleto see or find.4)(n) [C] - a person who carefully studies the topicto find new facts or information.5)(n.) [U] – the process of something being madeworse.6)7)8)(n.) [U] - the state of being safe and protectedfrom danger.(n.) [C; U] - a rise in the number.(n.) [U] - physical harm to something that makesit less attractive or useful.​