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Problem $4-16$ Calculating Rates of Return $[$LO $3]$

Refer back to the Serles EE savings bonds we discussed at the very beginning of the chapter to answer the following questions.

a$.$ Assuming you purchased a $$50$ face value bond, what rate of return would you earn if you held the bond for $20$ years untll it doubled in value?

Note: Do not round intermedlate calculations and enter your answer as a percent rounded to $2$ decimal places, e$.$g$.,32\mathrm{.}16.$

b$.$ If you purchased a $$50$ face value bond in early $2021$ at the then$-$current interest rate of $10$ percent per year, how much would the bond be worth in $2031?$

Note: Do not round intermediate calculations and round your answer to $2$ decimal places, e$.$g$.,3216.$

c$.$ In $2031,$ instead of cashing the bond in for its then$-$current value, you decide to hold the bond untll it doubles in face value in $2041.$ What rate of return will you earn over the last $10$ years?

Note: Do not round Intermediate calculations and enter your answer as a percent rounded to $2$ decimal places, e$.$g$.,32\mathrm{.}16.$

$\backslash$table$[[$a$.$ Rate of return,,$\%$