Greenhouse gases are the cause of Greenhouse effect.The greenhouse gases which include CO2, Methane etc. trap the heat in the Earth's atmosphere and don't allow it to escape.
The weapon is fitted with a Leupold Mark 4. The rifle is also similar in appearance to the TAC-338 rifle that Kyle used in real life. McMillan TAC-338A sniper rifle with Harris bipod, Leupold Mark 4 scope, and AN/PVS-22 Universal Night Sight - .338 Lapua Magnum. Kyle taking aim with the rifle. Right side of the rifle.
A telescopic sight, commonly called a scope, is a sighting device that is based on an optical refracting telescope.he first experiments directed to give shooters optical aiming aids go back to the early 17th century. For centuries different optical aiming aids and primitive predecessors of telescopic sights were created that had practical or performance limitations.