Consider the following binomial interest rate tree. Volatility of interest rates is 0.2.

Time 0	1	2	3
1.500%	2.500%	4.103%	x
	1.676%	y	3.854%
		1.843%	2.584%
			1.732%

a) calculate the rates indicated by x and y.

b) Calculate the value of a 4 year 3% annual coupon bond with par value of $1000.

c) if the bond in (b) is puttable during years 3 and 4, what would be its value?