profit is calculated by subtracting costs from Interest rate Securities investment refers to investors (as a legal person or natural person) to buy shares, bonds, funds, securities, and securities derivatives, in order to get dividends, interest, and capital gains investment behavior and investment process, is an important form of indirect investment.  In general, us interest rates fall and the dollar weakens. Us interest rates rise and dollar trends favour. A change in the price of U.S. Treasury bills, especially long-term Treasury bills, can help to predict the direction of the U.S. dollar. If investors think the us inflation is under the control, then under the existing Treasury bonds interest rate to attract, especially short-term Treasury bills, will attract investors, bond prices to rise. Suppliers who use the regular contribution plan will not borrow money from the bank of England until late February. When the programme ends, the rates offered may start to improve, but it will be a slow process. A historical experiment. In 1934, the Chrysler corporation of the United States first adopted a streamlined body design. In 1937, German design genius fernand porsche began designing cars resembling the beetle. Not only did the beetle crawl on the ground, but it also flew in the air, and its physical resistance was small. Dr Porsche maximized the merits of the beetle's appearance, making "vw" cars the representative work of streamlined cars at the time. The "golden age" of the beatles was the "golden age" of the car from the 1930s to the late 1940s. The independent of interest is of positive significance to show the active role of the fund users in the reproduction process.