concept of profit in economics In the face of market failure, coase has given the opposite answer: external-utility problems can be solved by explicitly using the market, without government intervention. And zhang wuchang is more absolute, he said that there is no so-called external utility, there is only unclear property rights. Anyway, coase brought revolutionary innovation to market concepts. He made it clear that the key to the market was not the "price mechanism" of impersonal machinery, but the power of participants in economic activity. In New York, the U.S. energy information administration (EIA) released data showing U.S. crude inventories fell by 649.5 million barrels a day in the week ended Dec. 15, beating expectations. Gasoline stocks rose by 12.37 million barrels, but the increase was less than expected. All of the cameras reviewed below have the standard features - Exposure Control (Bulb, Manual, Shutter-priority, Aperture-priority, Auto, Depth of Field), Shooting Modes (Close-up, Landscape, Sports, Portrait and Night), Metering Modes (Spot, Partial, Evaluative, Center-weighted), shoot in RAW, RAW+JPEG and JPEG, White Balance Control and Exposure Compensation. Most offer an 18-55mm, f/3.5-5.6 kit lens as standard. Quality control indicators include: gasoline antiknock property (research octane number, motor octane number, antiknock index), sulfur content, vapor pressure, contents of olefins, aromatics, benzene content, corrosion, distillation range, etc. In January 2014, the national general motors (gm) IV standard was used. The state administration of quality supervision and inspection and the national standards commission issued the mandatory national standards for motor vehicles in phase V. The plan is to be implemented at the end of 2016. The sulfur content is the most critical environmental protection indicator in vehicle gasoline. In order to further reduce the emission of vehicle pollutants, the national V standard lowers the sulfur content limit from 50ppm in the fourth stage to 10ppm, which is 80% lower. Manganese has the potential risk to human health, and the vehicle emission control system will also have adverse effects. According to the principle of prevention, the limit value of the manganese content indicator is reduced from 8mg/L in the fourth stage to 2mg/L, which stipulates that no artificial addition is allowed. In order to further reduce the photochemical pollution caused by the evaporation of gasoline, and reduce the gas intake system of the automobile engine, the national five standard reduced the level of olefin from 28% to 24% in the fourth stage. Due to the decrease of octane number caused by the reduction of sulfur and manganese, the number of gasoline used in phase V was adjusted from 90, 93 and 97 to 89, 92 and 95 respectively. At the same time, considering the development trend of the automobile industry, the index requirements of motor gasoline are added in the standard appendices. Micron, President and chief executive Sanjay Mehrotra said: "to Micron strong results mainly by the movement, application server and SSD revenue from double-digit growth, driven in addition gross margin and profit margins are improved." 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.