Answer each question based on the given data.

Year	Season	Time	Demand	DSD	SF	SI
2020	Winter	1	6
2020	Summer	2	3
2021	Winter	3	10
2021	Summer	4	8
2022	Winter	5
2022	Summer	6
2023	Winter	7

The regression equation based on a given data's CMA (N=2) is Y = 2 + X.

a. Calculate the seasonal index for the 2020 Winter (S1). S1 = _______________

b. Forecast Winter demand for 2020 using Winter's method with Alpha =0.5, Beta =0.5, and Gamma =0.5.

c. Suppose L4 =10, T4 =3, S5 =3, and S6 =5. Forecast Summer demand for the year 2022 using Winter's model with Alpha = 0.1, Beta = 0.2, and Gamma = 0.5.