Which Is True of the Level of CO₂ in Our

Multiple Choice

Which is true of the level of CO₂ in our atmosphere?

A) the level is currently over 386 ppm.
B) the rate of increase leveled out in 1976.
C) the level of CO₂ was much higher in 1955 than today.
D) the level of CO₂ is decreasing at 3.1% per year.
E) the rate of increase is not important as we have passed a threshold level to support life in the atmosphere.