Calculate implied volatility for the following put options to 4 decimals. Which one is the cheapest? Is there a volatility skew or smile present? clearly show the answer for each part Round to 4 decimals

JULY 13.65 TABLE 6.1 DCRB OPTION DATA, MAY 14 CALLS PUTS EXERCISE PRICE MAY JUNE JULY MAY JUNE 120 8.75 15.40 20.90 2.75 9.25 125 5.75 13.50 18.60 4.60 11.50 130 3.60 11.35 16.40 7.35 14.25 Current stock price: 125.94 Expirations: May 21, June 18, July 16 Risk-free rates (continuously compounded): 0.0447 (May); 0.0446 (June); 0.0453 (July) 16.60 19.65 JULY 13.65 TABLE 6.1 DCRB OPTION DATA, MAY 14 CALLS PUTS EXERCISE PRICE MAY JUNE JULY MAY JUNE 120 8.75 15.40 20.90 2.75 9.25 125 5.75 13.50 18.60 4.60 11.50 130 3.60 11.35 16.40 7.35 14.25 Current stock price: 125.94 Expirations: May 21, June 18, July 16 Risk-free rates (continuously compounded): 0.0447 (May); 0.0446 (June); 0.0453 (July) 16.60 19.65