[填空题]
Smith has saved $5000 from working a part-time job and wants to invest this money so that it grows over time. His bank offers a savings account that pays an annual interest rate of 4.2%, compounded quarterly.
1.Find how many years it will take for Smith's investment amount to double in value, rounding your answer to the nearest integer.
n= .
Smith wants his money to grow faster than this first option. His wants to invest the money so that it will double in value in 5 years. He considers an high-growth, higher-risk option, which pays an annual interest of r%, compounding half-yearly.
2.Determine the value of r required in this option, rounding your answer to two decimal places.
r= %.
