Bob Hill is the director of the customer service call center for Farmers\" Financial Company. A key task of Bob is to manage staff to answer and call customers in a timely manner. He needs to track the number of calls received and made by the center. He observes that the number of calls has been increasing and some parts of the year seem to be busier than others. Some customer service staffs are beginning to complain about the work load and suggest they cannot not always communicate with customers on time. Will additional customer service staffs be required to handle the apparently increasing demand? If so, how many new customer service staffs should be hired? To provide some insight into the nature of the demand to meet, Bob examines the total number of calls on a monthly basis for the last ten years. The data are listed in Excel file CallCenterData.xlsx. 1. Construct a time series plot of the data. Does the time series show any trend? 2. Is there seasonal component in the time series? Investigate this issue by constructing the autocorrelation function (ACF)