You buy a share of stock, write a $1-$year call option with X $=$ $$85,$ and buy a $1-$year put option with X $=$ $$85.$ Your net outlay to establish the entire portfolio is $$83\mathrm{.}3.$

Required:

What is the payoff of your portfolio?

What must be the risk$-$free interest rate? The stock pays no dividends.

Note: Round your answer to $2$ decimal places.