People with home septic systems often flush several cups of a powdered substance down their toilets every month or two to keep their systems healthy. These powdered substances most likely contain
A) bacteria and enzymes that help break down wastes.
B) chlorine and other disinfectants that help to prevent soil contamination.
C) chemicals that bind to heavy metals to keep them from leaching into the soil.
D) acids that help to clean the insides of the walls of the pipes and septic tank.
Question 2
The recent Cairo and Stockholm population conferences in 1994 and 2014 found widespread agreement that the greatest way to help developing countries was to
A) limit their population growth through improving women's health and education.
B) increase their use of modern medicine.
C) improve their agricultural productivity.
D) limit their environmental degradation.
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