In April 2017, Facebook's stock price was about $156. An eight-month call on the stock, with an exercise price of $156, sold for $21.18. The risk-free interest rate was 1% a year. How much would you be willing to pay for a put on Facebook stock with the same maturity and exercise price? Assume that the Facebook options are European options. (Note: Facebook does not pay a dividend.) (Do not round intermediate calculations. Round your answer to 2 decimal places.)