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.
-According to various lines of evidence, our species emerged about 160,000 years ago. At that time, temperatures were about _°C cooler than they are now, and the carbon dioxide level was about _ ppm.

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.
-According to various lines of evidence, our species emerged about 160,000 years ago. At that time, temperatures were about _______°C cooler than they are now, and the carbon dioxide level was about _______ ppm.