Driving theory questions

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Which two exhaust substances contribute to the formation of tropospheric ozone?

  • Incorrect: Carbon monoxide and carbon dioxide.
  • Correct: Hydrocarbons and nitric oxide.
  • Incorrect: Carbon monoxide and nitric oxide.

Along with nitric oxides, the hydrocarbon emissions contribute to the formation of tropospheric ozone.” (Driving Licence Book, 19th Edition, page 228)


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