Predicting the future is usually based on historical performance. Planners are required to clean the history and record regular and irregular events and activities to help understand the events that are repeated every year and therefore need to be factored-in in the forecast. Example(s) of such activities that must be recorded are: a. All of the options b. Available information technology c. Available capacity at the factory d. Required resources including labor e. Sales promotions, price changes, weather changes, etc