Question 4: A management analyst is using weighted moving average to predict the demand for Samsung M11 mobile phone. The data on the EXCEL spreadsheet shows the demand for Samsung M11 mobile phone for a 12-month period in 2019. Use the data to answer the following questions
a) Calculate 3-monthly moving average from January to December.
b) Calculate the 4-monthly moving average from January to December.
c) Calculate the 3-month weighted moving average for all the months if the weightings are given as
Fig: 1