Who is razi plss elaborate it

Al Razi is considered the “original portrayer” of smallpox. While serving as the Chief Physician in Baghdad, he was the first to describe smallpox and to differentiate it from measles. He wrote a treatise on the subject: “Kitab al Judari wa al Hasbah”. This book was translated more than dozen times into Latin.

john maynard keynes developed new economic theories in response to the stock market crash of 1929. great depression of the 1930s. first and second world wars. economic boom of the 1950s.