Rule 72 is:
A. Ausefulformulafor estimating howlongitwill take to double a sum at a given interest rate
B. Ausefulformulafor estimating howlongitwill take to triple a sum at a given interest rate
C. Ausefulformulafor estimating howlongitwill take to graphically represent the time value ofmoney
D. Ausefulformulafor estimating howlongitwill take to make the future value of deposited money