I am lost in the middle of a vast desert in my swim shorts. There is nothing anywhere around me as far as you can see. In front of me is a 12volt battery (say lead acid) with no markings or other indicators of polarity. there are 2 wires long enough to make a connection to the emergency tranmitter next to it, also 12 volt. If it is wired up wrong the transmitter will be destroyed instantly. If it is done right, then i will be rescued. How can i make the right choice.