OPSC 2018 Solved Paper

Water vapour is the most abundant Green House Gas (GHG) in the atmosphere. It comprises about $4\%$ of atmospheric volume. Other important Green House Gases with their per cent volume are Carbon dioxide $\left(0.03\%\right);$ Nitrous Oxide $\left(0.0003\%\right)$ and Methane $\left(0.00017\%\right)$.