The nitrogen cycle is the process by which nitrogen is converted between its various chemical forms. This transformation can be carried out through both biological and physical processes. Important processes in the nitrogen cycle include fixation, ammonification, nitrification, and denitrification. The majority of Earth's atmosphere (78%) is nitrogen, making it the largest pool of nitrogen.
Topher Grace. Christopher John Topher Grace (/ËtoÊfÉr/; born July 12, 1978) is an American actor. He is known for his portrayal of Eric Forman on the Fox sitcom That '70s Show, Eddie Brock/Venom in the Sam Raimi film Spider-Man 3, Carter Duryea in the film In Good Company and Edwin in the 2010 film Predators. 1 Early life.
Grace Anna Goodhue Coolidge was the wife of the 30th President of the United States, Calvin Coolidge. She was the First Lady from 1923 to 1929. She graduated from the University of Vermont in 1902 with a bachelor of arts degree in teaching and joined the Clarke Schools for Hearing and Speech in Northampton, Massachusetts to teach deaf children to communicate by lip reading, rather than by signing. She met Calvin Coolidge in 1904, and the two were married the following year. As her husband advanc