Hi everyone it's been a few years since I've flown and I've forgotten some things.

-What is the difference between the high rates and the low rates? When should I use one or the other?

-My planes have not flown in a few years, should I be concerned about the health of their batteries? I have charged them up and decharged them, should that be enough?

-My trainer has an O.S. 46LA in it, My Extra 300 has a Magnum .75 two stroke in it and my Cessna 182 Skylane will have a Saito 125 in it, can I use the same fuel for all of them?

-After I've gotten my skills up to par again with my trainer I'm planning on giving my Extra her maiden flight. Would I be wise to mix some rudder in with the ailerons? I'm using a Futaba T6XA.

Thank you in advance for the help.

-Eric