According to the rule of 72, mc007-1.jpg which statement is true?
1. An investment of $3,100 will double in 12 years at a compound interest rate of 5%.
2.An investment of $9,000 will double in 10 years at a compound interest rate of 7%.
3. An investment of $4,500 will double in 8 years at a compound interest rate of 9%.
4. An investment of $3,000 will double in 4 years at a compound interest rate of 12%.