Compute a three-period moving average forecast given demand for shopping carts for the last five periods. (Round all your answers to two decimal points.) Period 1 2 3 4 5 Demand 42 38 42 37 45 Forecast Period 4 Forecast Period 5 Forecast Period 6 If actual demand in period 6 turns out to be 42, the moving average forecast for period 7 would be Forecast Period 7