Methane as a greenhouse gas[edit] Methane in the Earth's atmosphere is a strong greenhouse gas with a global warming potential of 29 over a 100-year period. This means that a methane emission will have 29 times the impact on temperature of a carbon dioxide emission of the same mass over the following 100 years.
Laptop computers. On laptop computers, the Fn key is almost always located on the bottom left-hand side of the keyboard, next to the Ctrl key. Chromebooks. Not all Chromebooks have an Fn key. For those that do have an Fn key, it is often found near the spacebar.
Test your Fn key. One of the easiest ways to do this is by pressing Fn and Esc at the same time. This toggles the sound on your computer on and off, and will show a speaker icon on your screen if it works. Step. Press Fn and Num lock at the same time if the Fn key still does not work. Use the F11 key if your laptop has no Num Lock key.