A European call option and put option on a stock both have a strike price of $20 and an expiration date in 7 months. Both sell for $3. The risk-free interest rate is 8.9% per annum, the current stock price is $19, and a $1 dividend is expected in one month. What is the present value of the arbitrage opportunity open to a trader?

Enter your answer rounded to two decimal places, skip the $ sign. For example, if your calculation results in $98.1234567, you only need to enter 98.12.