Time Series (Statistics)

I need a solution for a time series problem.

Only one problem and this one requires R using.

Problem is beloew :

In the R package astsa there is a data set called flu which gives the number of deaths per 10,000 people in the United States due to pneumonia and influenza. The data is recorded by month for 1968-1978. There is a slight trend so remove it by fitting a polynomial of order 1. Now fit a seasonal component to the detrended data using a sum of harmonics. Show the plots of the detrended data, the estimated seasonal component, and the residuals after the trend and seasonal components have been removed. You do not have to fit a model to the residuals. Give the values of asj , acj , and ?j that you used in your final model.