I am trying to hook up a 12 volt processor fan to make a cheap propeller for a toy boat. I need to know how I can do this safely and effectively. I have three batteries and negative and positive from the fan. Please tell me the step by step instruction to electrically wire all these to achieve what I wish for. How to hook up a nine volt battery to two 1.5 volt C batteries to achieve 12 volts? I would really appreciate useful information pertaining to my query at the earliest. Thanks.