Is it better to leave the laptop closed up when I'm done using it or to leave it on and open?
If it's plugged into the wall it doesn't really matter. If the laptop is closed up it should put itself to sleep, so you'll have to wait for it to wake up again if you want to open it up and use it. The plus side of this is that it isn't using much battery power during this time, but as I said if it's plugged into the wall it really doesn't matter. I close mine up, just because I'm clumsy and tend to spill things on keyboards.
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