33128
The critical masses of two other readily available isotopes , Am and Am , are relatively high – 57.6 to 75.6 " kg for Am and 209 " kg for Am .
 Am, Am, Am, Am
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Am, Am, Am, Am