Please choose the correct ending to complete the given sentence: Computers and Electronics: [header] How to charge an ipad [title] Prepare your charger. [step] Plug the usb cord, provided with your ipad, into an adapter. [title] Locate an outlet.

Ending1: [step] If you need to charge an ipad, the outlet may be located on the side of the device, along the back, or behind it. [title] Plug the ear jack into the outlet's input position. Ending2: [step] Plug the adapter into said outlet. [title] Plug the end of the cord into your ipad. Ending3: [step] Most computers in the us have a charging port that you plug your ipad into. [substeps] Computers in the uk use a minimum of 260psi output. Ending4: [step] An adapter is a unit with a run of some sort, their charging source should be located directly beneath your usb plug-in. [title] Plug your ipad into the adapter.

Answer format: ending1/ending2/ending3/ending4