PA Mining Law - Sections 416-420
Practice test questions for the PA Mine Officials' Exam


Progress Indicator:
Question 3 of 15

3.  Sudden changes in atmospheric pressure may cause temporary fluctuations in the ______________ reading.

Choices:
  1. Carbon monoxide
  2. Methane
  3. Nitrogen dioxide
  4. Oxygen
  5. Al of the above


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