As slowly as is needed to be safe.
Yes, unnecessary backing is frowned upon.
The law in every state is very clear about backing. The person backing up/out is at fault and responsible for any damages, regardless of the other vehicle's speed and/or position. It's also known as:"Limitations on backing".
Should look over right should as i bak up
You should always be looking behind you when backing up. You don't look forward when reversing because you're not moving in a forward direction.
EVERYTHING and everyone who might be behind you.
you should mate her when she starts backing up to the male.
backing up data