1. Rubber tube aging Compression ratio refers to the ratio between the total volume of the cylinder and the volume of the combustion chamber, which indicates the degree of gas compression in the cylinder when the piston moves from the lower stop to the upper stop. Compression ratio is an important parameter to measure the performance of automobile engine. In the early 20th century, famous American economist elvin fisher developed the theory of economic gain. In its book "the nature of capital and yield", first, the concept of yield is analyzed in terms of the performance of earnings, and three different types of benefits are proposed: ^ h h, however, interest rates are still significantly lower than in November 2015, when an average of 2.62 PC. Modern economy, the interest rate as the price of money, not only restricted by many factors in the economic and social, and changes in interest rates to have a great impact on the economy as a whole, as a result, modern economists are studying the interest rate decision problem, pay special attention to the relationship between the variables and the balance of the economy as a whole, the interest rate decision theory has experienced the classical interest rate theory, Keynes's interest theory, interest rate in loanable funds theory and is-lm analysis as well as the contemporary evolution of dynamic interest rate model, the development process. It said the budget crunch was necessary to undermine Britain's fiscal position in the wake of the 2008 financial crisis. But the fund questioned whether the fiscal sector relied on spending cuts to reduce the deficit, adding that it should be seen as part of further measures. At the same time, because of the surplus value for money is the commodity that only appeared well after the completion of the production process, it is further considered capitalists in order to produce goods all prepaid capital input by the capital employed are not included in the cost price (including those fixed capital). Not only that, the flow of goods from the production process into the process, in order to engage in sales activities to additional capital (including pure circulation costs), therefore, the residual value is considered to be not only all capital in advance in the field of production, but also be regarded as include all of the advance in the field of production and circulation of capital brought together.