Which element jas altered the carbon cycle?
a) oxygen
b) nitrogen
c) human
d) sulfur
What is the projected amount of CO2 in the atmosphere in 2060 based on the stimulation?
a)309
b)550
c) 604
d) 700
What is the stimulated amount of CO2 in the atmosphere when fossil fuel use is increased to 3.5%
a) 400
b) 550
c) 604
d) 755
