Question

if the rate of carbon dioxide concentration remains the same as from 2000 to 2015, what can we expect the co2 concentration to be in the year 2025? a 410 ppm b 420 ppm c 430 ppm d 440 ppm

Explanation:

Step1: Find the change from 2000 - 2015

From the graph, in 2000 the CO₂ concentration was around 370 ppm and in 2015 it was around 400 ppm. The change in 15 years (2015 - 2000=15) is 400 - 370 = 30 ppm. So the average annual increase is $\frac{30}{15}=2$ ppm per year.

Step2: Calculate for 2025

From 2015 to 2025 is 10 years. If the rate remains 2 ppm per year, the increase from 2015 to 2025 is $2\times10 = 20$ ppm. Since the concentration in 2015 was around 400 ppm, the expected concentration in 2025 is $400+20=420$ ppm.

Answer:

B. 420 ppm