profitable mining “We’re very proud of the way that the glass industry has come together to face the challenge of energy efficiency and decarbonisation - which will continue to define all manufacturing and markets for the coming decades. Famous British economist hicks and others argue that the above theory did not consider the factor of income, and therefore unable to determine the level of interest rates, in 1937, and puts forward the is-lm model on the basis of general equilibrium theory. It establishes a theory of interest rates and income at the same time that the four factors of savings and investment, money supply and monetary demand interact. Gas vehicles mainly include liquefied petroleum gas vehicles (LPG vehicles or LPGV) and compressed natural gas vehicles (CNG cars or CNGV). As the name suggests, LPG cars are fueled by liquefied petroleum gas (LPG) and CNG is powered by compressed natural gas. The CO emission of gas vehicles is more than 90 percent less than the gasoline car, the hydrocarbon emission reduction is more than 70 percent, and the nitrogen and oxygen emission reduction is more than 35 percent, which is the current relatively practical low emission vehicle.