LLarry bought a car for $$40,000$ at $"0\%"$ interest for $60$ months $($$$40,000$ in total was paid in $60$ equal monthly payments$).$ The financing was done through Flames Financing Co$.$ If he had paid cash for the car in the beginning, he would have paid $$34,000.$ Determine the annual interest rate he is paying on this car loan.

Group of answer choices

$6\mathrm{.}6\%$

$6\%$

$5\mathrm{.}2\%$

$5\mathrm{.}8$