What are the uses of anhydrous ammonia in the united states and what
are their respective percentages. Also who produces anhydrous ammonia
and where can I find out how much is produced. 
And what are the alternatives to using anhydrous ammonia for farmers in
Iowa.
What are the requirements of farmers who use ammonia on their farms?
How is Anhydrous ammonia applied to crops and what are the
alternatives to using it.
Is there a place that counts the fatalities per year attributed to ammonia?