A three$-$month European call option on a non$-$dividend paying stock in Universal Widget Inc. with a strike price of $$1\mathrm{.}30$ has current price of $$0\mathrm{.}8557.$ The continuously compounded risk free rate is $0\mathrm{.}5\%$ p$.$a$.$ The current stock price is $$1\mathrm{.}20.$ Assume all the Black$-$Scholes assumptions hold. Calculate the implied volatility for the underlying stock to within $1\%$ p$.$a$.$