As a percentage of weight, what elements makes up most of our bodies?
Phosphorous
Carbon
Hydrogen
Oxygen
Lack of _______ leads to goiter
Iodine
Mercury
Sulfur
Potassium
What chemical is added to many city water supplies that helps protect teeth?
Chlorine
Apatite
Halite
Flourine
What is the second leading cause of lung cancer in the U.S.?
Radon
Sulfur Dioxide
Asbestos
