According to Figure 2, the concentration of atmospheric COz in 1750 was closest to which of the following?
F
240 ppm
pheric mass face to r points the past ate will
(G
260 ppm
(H
270 ppm
300 ppm
F
240 ppm
pheric mass face to r points the past ate will
(G
260 ppm
(H
270 ppm
300 ppm