Solve for the unknown number of years in each of the following: intermediate calculations and round your answers to $2$ decimal places

$\backslash$table$[[$Present Value,Years,Interest Rate,Future Value$],[$$$,8,\%,$$$,1,075],[500,,12,\%,1,836],[750,,18,\%,294,671],[17,800,,14,\%,320,610],[20,900,,,,]]$