Files may be assigned to groups for processing in an efficient manner. The method provides for displaying a plurality of panes within the single window, receiving a user input, displaying at least one pivot point input location in response to the user input, receiving a twist input, and modifying the plurality of panes in response to the twist input. Optionally, the gas source and the reducing gas are associated with a direct reduction process for converting iron oxide to metallic iron in a reduction furnace that utilizes the reducing gas, optionally after some modification, and produces the gas source. The resilient device is disposed below the slider for exerting a resilient force on the slider to move the slider.