I just bought a Macbook Pro 15inch Retina I just have a few questions. My battery only lasts around 4 hours, all I do is browse the web on firefox, no heavy apps, is this normal? My laptop heats up significantly, when I charge it and use it at the same time, is this normal?? Is it ok for the battery and laptop to use the laptop while it is plugged in? I read somewhere continuously using a laptop while it's plugged in, is bad for the battery. Thanks in advance for your help guys.