Compounding Interest

• What is a non-interest-bearing account? (A non-interest-bearing account is one that pays no interest on the principal.) 
• What is interest? (Interest is the price of using someone else’s money.) 
• What is compound interest? (Compound interest is interest computed on the original principal and accrued interest.) 
• What interest rate would a savings account or a low-risk investment likely pay— would it be a low, medium, or high interest rate—and why? (They would each pay a low interest rate because of the risk-reward relationship.) 
• What does the rule of 72 estimate? (The rule of 72 estimates the number of years it will take for a financial investment—or debt—to double in value at a given annual interest rate.)
•  Checking account （银行）支票账户； 一般没有利息， 或者利息极低
• 如果一个投资固定的年回报率是8%， 要花几年时间才能使原来的投资翻8倍？（27年）