Just bought my first laptop, I'm wondering - 1) Is it ok to unplug the power or plug it back in when running? 2) My battery is slowly losing its charge(down to 96%). I'm sure this is just because I have only been using it on AC. So, what should I do to keep the battery in good shape? Run it on the battery for a few hours every week? Down to what % charge? Thanks. P.S. It's a lenovo, I couldn't find this info anywhere on their site.