Solve for the unknown number of years in each of the following:

Note: Do not round intermediate calculations and round your answers to $2$ decimal places, e$.$g$.,32\mathrm{.}16.$

$\backslash$table$[[$Present Value,Years,Interest Rate,Future Value$],[$$$,11,\%,$$$,1,955],[1,100,,9,\%,4,550],[2,791,,14,\%,395,620],[34,505,,21,\%,223,916],[34,200,,,,]]$