Maintaining your education is important, especially in a career that demands licensing exams. Prove you’re an expert operator by answering this question and others from our Exam Study Guide Series. Take a look at this question on Public Water Systems along with an explanation of the correct answer.Sample question:Which ion does ion exchange softening add to the water?A) Sodium
B) Calcium
C) Aluminm sulfate
D) MagnesiumThe correct answer is A.About the author: Drew Hoelscher is the program director of drinking water operations at the Environmental Resources Training Center (ERTC) in Edwardsville, Illinois.
