According to readings from the Mauna Loa Observatory,CO₂ concentrations in May 2013 exceeded_________ for the first time during the last 800,000 years. A)100-ppm B)200-ppm C)300-ppm D)400-ppm

Question

Quizplus · Accepted Answer

According to the statement, CO2 concentrations exceeded for the first time during the last 800,000 years in May 2013. The question asks for the concentration level, and only option D, 400-ppm, matches with the given information. Therefore, D is the correct choice.

According to Readings from the Mauna Loa Observatory,CO2 Concentrations in May

According to Readings from the Mauna Loa Observatory,CO₂ Concentrations in May