3.
The Battery.
With your model you will get a battery that is matched to your charger, in my case, its a 7.2v 6-cell Nickel - cadmium battery, i wont go into the exact chemistry in there, just that one part of the battery is nickel, the other being cadmium. Before you run your model, you need to charge your battery by plugging it in to your charger.
Ensure wall socket is turned off before plugging anything into it
Pug your charger into the wall and connect the battery to it as pictured, then turn the charger on, ensuring that the battery is in a safe place, such as on a table, when you turn the charger on at the wall, if it has a light on it, this light will come on, telling you that the battery is charging.
Towards the end of its charge, typically after 12 hours or so with a slow charger your battery pack will be warm, do not worry, this is normal and no cause for concern.