Refer to the figure.
The figure shows the temperature (in °C, relative to modern temperature) and the concentrations of carbon dioxide (in ppm) and methane (in ppb) over the past 400,000 years.
- Ten thousand years ago, the concentration of carbon dioxide was about _______ times that of methane.
A) 5
B) 20
C) 50
D) 500

Question

Refer to the figure.
 The figure shows the temperature (in °C, relative to modern temperature) and the concentrations of carbon dioxide (in ppm) and methane (in ppb) over the past 400,000 years.
- Ten thousand years ago, the concentration of carbon dioxide was about _______ times that of methane.
A) 5 
B) 20 
C) 50 
D) 500

Quizplus · Accepted Answer

The Answer of Refer to the figure.
 The figure shows the temperature (in °C, relative to modern temperature) and the concentrations of carbon dioxide (in ppm) and methane (in ppb) over the past 400,000 years.
- Ten thousand years ago, the concentration of carbon dioxide was about _______ times that of methane.
A) 5 
B) 20 
C) 50 
D) 500

Refer to the Figure