dipstick

This might sound like a dumb question but I figured I would ask. If I check my cars oil while parked on a slight incline (driveway) will the reading on the dipstick be higher or lower than the actual oil level? I know to get an accurate reading you need to be on a flat level surface but I was...

Anyone know how much oil to add to bring bring sump oil level from the bottom of the cross-hatched dipstick range to the top? Halfway to the top?