Answer: Nitrogen
Explanation: Nitrogen makes up 78% of the atmosphere, Oxygen makes up 21%, and Argon 0.9%.
Water vaper makes up between 1-4%, depending on the region.
Carbon Dioxide makes up only about 0.04%.
Assuming that the entirety of the force is opposite the static friction, then the couch should begin sliding as the applied force overcomes the couch's static friction with what it's making contact with.
Its 1.73793151243 as a whole but if rounded it is 1.74