Using Apple Inc. financial data, perform the following procedures and present the results. Remember that the data for Apple's latest quarter will be used for testing the forecasts (test data) and not used for developing the forecasting equations.

a. Prepare forecasting equations for Sales Revenue (y), using Simple Regression Analysis based on Gross Domestic Product, Personal Income, Government Current Receipts and Expenditures, Foreign Transactions (Current Receipts from the Rest of the World), and Gross Saving as independent variables (x). Remember that your independent variables will have to lag one period. You must develop six separate forecasting equations for this section.