Problem $5-7$ Calculating the Number of Periods $[$LO$4]$

At $6\mathrm{.}6$ percent interest, how long does it take to double your money? $($Do not round intermediate calculations and round your answer to $2$ decimal places, e$.$g$.,32\mathrm{.}16.)$

At $6\mathrm{.}6$ percent interest, how long does it take to quadruple it$?($Do not round intermediate calculations and round your answer to $2$ decimal places, e$.$g$.,32\mathrm{.}16.)$