I am building a prototype which has an arduino uno in a project enclosure on one end, and a bunch of sensors and actuators about two meter away, connected by a 10 wire-ribbon (like this: http://static0.ponoko.com/images/thumbnails/2011/07/30/004741_file.jpg?&s=c3fc6a1a30d78ad0). This wire is going to carry 9V, 5V, GND, and several digital data streams (0-5V). So there are no analog inputs through the wires.The current that will be flowing through will mostly be small amounts (i.e. 20mA for the data lines) and some bigger amounts (max. around 400mA for the 5V to GND). Being a relative beginner in electronics, I was wondering whether I should try to keep certain wires apart, because of interference or electromagnetism or whatnot (as the wires are directly next to each other on the ribbon). For instance, keeping the data lines away from the 9V, or keeping them apart from each other? Or doesn't interference play any significant role at these voltages and currents? Thanks!