We are using Winter’s method and monthly data to forecast the GDP. (All numbers are in billions of dollars.) At the end of January 2005, L t = 600 and T t = 5. We are given the following...

We are using Winter’s method and monthly data to forecast the GDP. (All numbers are in billions of dollars.) At the end of January 2005, L_t = 600 and T_t = 5. We are given the following seasonalities: January, 0.80; February, 0.85; December, 1.2. During February 2005, the GDP is at a level of 630. At the end of February what is the forecast for the December 2005 level of the GDP? Use α = β = γ = 0.5.