Buffelhead's stock price is $216 and could halve or double in each six-month period. A one-year call option on Buffelhead has an exercise price of $163. The interest rate is 21% a year.

1. b-1. Now calculate the option delta for the second six months if the stock price rises to $432.

2. b-2. Now calculate the option delta for the second six months if the stock price falls to $108. (Round your answer to 2 decimal places.)