Consider a six-month put option with a strike price

Consider a six-month put option with a strike price

Subject: Business    / Finance   
Question
Consider a six-month put option with a strike price of 60 on a stock whose current price is 60. There are two time steps of three months and in each time step the stock price either moves up by 15% or down by 20%. The risk free rate of interest is 5.5% per year with continuous compounding.

A.    Compute the value of a European put option.
B.    Compute the value of an American put option.
C.    Compute the value of the right of early exercise.