what is the reticular activating system Why? Micron quarterly revenue and net income historical data Interest rate, in the form of expression, refers to the ratio of the amount of interest to the total amount of borrowed capital in a certain period of time.  the interest rate is the interest level per unit time of the unit currency, indicating the interest rate. Economists have been looking for a theory that can fully explain the structure and change of interest rates. Interest rates are usually controlled by the central bank of the country and administered by the federal reserve board in the United States. Today, interest rates are one of the important tools for macroeconomic regulation. In addition, the national standard has strict regulations on the content of various chemical components of gasoline such as benzene and olefins. Alkenes are high in content, which can produce gelatinous substances in the process, and accumulate in intake manifold and valve catheter. When the engine is in normal working temperature, there is no abnormal phenomenon; When the engine has cooled for some time, the glial will stick the valve inside the valve tube. When you start the engine, you will have a top valve phenomenon. The toxic benzene content should not exceed 1%.