In the near future, the car owner who has changed the gasoline pump or unloaded the gas pump will not panic if there is a gasoline smell in the car. It is likely that the residue has not been cleaned up after the removal of the vehicle. The probability of such a situation is small, and the general replacement cycle of the gasoline pump is 100 thousand kilometers. But the gasoline filter is connected with the gasoline pump. The replacement cycle is shorter and the gasoline pump needs to be removed when replacing. In this case, simply check the installation of the gasoline pump and clean the surrounding area. The investment quantity is the decreasing function of interest rate, saving is the increment function of interest rate, and the change of interest rate depends on the equilibrium point of investment quantity and saving amount. Keynes's theory of money supply and demand decided that interest rates were a monetary factor rather than an actual factor. Investment in securities provides an important channel for the society to raise funds, which is an effective way for enterprises to raise direct financing. breakthrough, but said, the final agreement was established to minimize the trade barriers, and to provide enough time to implement change.