Worldwide CO2 emissions in 1990 were 22.5 billion tonnes.
Worldwide CO2 emissions in 2010 were 33.6 billion tonnes.
Given that A A\,A billion tonnes is the CO2 emissions n n\,n years after 1990.
Using a linear model, form an equation linking A A\,A with nnn.
In 2016 worldwide CO2 emissions were 35.7 billion tonnes.
Comment on the suitability of your model in light of this information