This is a part of literature review of a research paper for publication in a journal. I need you please to do systematic review for the following headings: 1. History of PANDEMICS of the last two thousand years (this part should explain and discuss different pandemics that happened during the last two thousand years around the world. So, discussion for each pandemic should cover these points: how pandemic is started, how long it lasted, country of its origin, its consequences on individuals and countries, connections between pandemics if there is any, discussion about pandemic should be on ascending order from the oldest pandemic to the newest pandemic which is COVID-19)- use 2 pages for this part. 2. History of Coronavirus including COVID-19 (this part should explain and discuss coronavirus history and COVID-19 in details, difference between terms (coronavirus and covid-19) as well, impacts of Corona virus, factors of coronavirus. Use 2 pages for this part. 3. Symptoms of Covid-19 (this part should explain and discuss all symptoms that mentioned in existing literature of Covid-19). Use 2 pages for this part. 4. Variants of Covid-19 (this part should explain and discuss different variants of Covid-19 in details). Use 2 pages for this part. For references: please use journals’ articles from different contexts and updated papers, official websites for news such BBC and CNN. Try to use articles from high ranked journals in different areas. Use 18 references. Please use in-citations for more reliability and validity for the discussion.