. If you deposit 100 into a saving account one week and add 50 to the account each week for two weeks. At the end of the first week you earn seven days interest one hundred dollars.
             There are different loan markets. One for consumer loans, home mortgages, corporate bonds, state and local government bonds and foreign loans, and they also have their own interest rates that rise and fall. The different interest rates differ by supply and demand. Interest rate rise if 1. The demand for loans increases. 2. The amount of money available for loans decreases.
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