And although you can't build from Planning Sets, they will allow you to gather bids from contractors, arrange your furniture in the plan, analyze traffic patterns and gauge the site lines on your lot.
A: Earth's atmosphere, which is around 300 miles thick, is mainly made of nitrogen and oxygen, although there are many other trace substances in its composition. Trace substances make up only 1 percent of the bulk of the atmosphere while nitrogen (78 percent), oxygen (21 percent) and argon (1 percent) make up the rest. Continue Reading
Most of the air in our atmosphere is made of nitrogen gas. But there are other gases in our atmosphere that contain nitrogen as well. They make up only a small fraction of the air molecules in our atmosphere, but their numbers are growing and, even in small amounts, they are causing huge changes in our planet.