Anita Limited has shared their annual sales revenue over the last 6 financial years from 2015 to 2020 

You are required to;

a. Using linear trend equation forecast the sales revenue of Anita Limited for 2021.       

b. Calculate the forecasted sales difference if you use  3-period weighted moving average designed with the following weights: 

2018 (0.1),

2019 (0.3) and 

2020(0.6).  

(note: please provide with the details answer with formulas with clearly explanation )

Year 2015 2016 2017 2018 2019 2020 Sales ($ 000) 4500 5100 4900 5400 5670 6000