the president of state university wants to forecast student enrollment for this academic year based on the following historical data 5 years ago enrollment is 15000 , 4 years ago enrollment is 16000 , 3 years ago enrollment is 18000. 2 years ago enrollment is 20000 and last year enrollment is 21000. a- What is the forecast for this year using a 3-year weighted moving average where the weights are halved in a descending order from newest to oldest ? b. What is the forecast for this year using the trend line for these data? c. using the MAD find which forecasting technique may be appropriate for this