I'm quite new to mac. I was told to put my computer(macbook pro 13 inch 2012 model) in sleep mode when im not using it instead of shutting it down. however my battery drains while it is sleep mode. i will leave my computer in sleep mode for about 2 or 3 hours and when i open it and great deal of the battery has drained. is there a way to cut down on the battery drain while it is in sleep mode. or is it better to just shut it down.