please use excel and show formulas! thank you!

5. ( 2 points) Using Holt's method with a smoothing constant a=0.3 and a trend constant =0.6, what is the forecast for 1/2/2016 ? It's okay if your forecast goes negative at some points (although it shouldn't be negative for 1/2/2016 ). 6. ( 2 points) What is the RMSE if we use a smoothing constant a=0.3 and a trend constant =0.6 ? 7. (6 points) What are the optimal constants a and (use increments of .05 for each)? What is the RMSE when these optimal constants are used