Read the following article, and answer the questions. (Upload a file with your answers before the submission deadline.)
Jorgensen, T.J. Forget Fukushima: Chernobyl still holds record as worst nuclear accident for public health. The Conversation April 25, 2016.
Forget Fukushima: Chernobyl still holds record as worst nuclear accident for public health (Links to an external site.)
Question 1:
There are 7 levels on the  IAEA  scale of nuclear accidents. List and define the criteria for each of the 7 levels of the scale, and provide one historical example of an accident for each level. Give the name, location, and date of each accident, as well as a brief description of what caused the accident.
Question 2:
For each of the 7 accidents you described, list the radioisotopes that were released into the environment and the physical half-lives of those radioisotopes. How important do you think a radioisotope’s physical half-life is to the long term health consequences of environmental contamination by that isotope? Explain your answer. 
Question 3:
Of all the radioisotopes you listed in Question 2, which one would concern you the most, and which one the least. Explain your rationale.