Which statement best describes radon?
a. a radioactive gas emitted from the Earth's crust
b. an odorless, colorless gas that is a major source of pollution
c. carbon-based source of energy derived form the deposits in the Earth
d. an extremely reactive form of oxygen that is a major constituent of smog
Question 2
Common conditions that lead to lead poisoning include all of the following except:
a. older homes with dilapidated lead paint.
b. eating paint chips that contain lead.
c. ingestion of household dust that contains lead.
d. drinking water that has passed through corroded plumbing.
