average profit margin restaurant Under the theoretical framework of the theory, the theory of commodity market equilibrium and the monetary market equilibrium of Keynesian theory are unified. Marx's theory of interest rate decisions from the perspective of the source and essence of interest, taking into account the institutional factors in the role of interest rate decisions of interest theory, its theoretical core is the interest rate is determined by the average profit margin. Marx believed that under capitalism, interest is a part of profit and a form of conversion of surplus value. Microsoft's Surface Pro, Surface Laptop, Surface Book and Surface Studio are the main products of Microsoft's Surface series, but there is a clear difference in the share of the devices. The Surface Pro products account for the highest share (79.9%), the Surface Book (7.5%), Surface Laptop (2.0%), and Surface Studio (0.2%). The investment in securities is conducive to improving the operation and management of enterprises, improving the economic and social visibility of enterprises and promoting the rationalization of enterprises' behaviors. After all, with tighter regulation and tight capital, high interest rates and high limits mean high risk, but investors should also be careful not to put money in one basket. The development of automobile modeling was better aerodynamic design combined with seating comfort to be properly, in full consideration to the above two key problems, on the basis of efforts to develop new technology in the field of human body engineering, in order to design and make cars more perfect, more outstanding for the target. One day, the car cab will form a "glass cover" with beautiful curves. It is reflected in the geometry of the body, the round and the streamline. At that time, the paint of car colour will reflect soft feeling and transparent feeling in the bright-coloured, so will be more pleasing to the eye. The API said gasoline stocks rose by 200.10 million barrels last week, an increase of 2231, 000 barrels. Refining inventories fell by 2.58 million barrels last week, or 13.27 million barrels.