Which heavy metal is used in the manufacture of thermometers, dental fillings, and batteries?

Which heavy metal is used in the manufacture of thermometers, dental fillings, and batteries?
 a. lead
  b. cadmium
  c. mercury
  d. selenium

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A toxic chemical produced by certain kinds of molds is:
 a. arsenic.
  b. aflatoxin.
  c. asbestos.
  d. sulfur dioxide.

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Dose dependency depends upon which of the following factors?
 a. the amount of toxin in which a person is exposed
  b. the length of time a person is exposed
  c. how many times a person is exposed
  d. all of these choices

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A poisonous substance that can damage the brain and central nervous system is a(n):
 a. neurotoxin.
  b. petrochemical.
  c. organochlorine.
  d. mutagen.

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Why are there discrepancies between the general public opinion and the established scientific evidence concerning environmental hazards?
 a. People perceive risks according to how the risks affect their own lives.
  b. The general public is too concerned with large groups of people.
  c. The general public has a tendency to complicate matters of environmental risk.
  d. all of these choices