My mom has a macbook air 2010, her startup disk is full. I don't know what to do for it. She often likes to download tons of apps, we're guessing thats' what's causing the built up in her ram. Another thing is whenever i delete unwanted files/pictures the trash can isn't getting full, but it's asking me for her admin password every time. How do I fix this? How do I lower the startup disk from not being so full?