What is an closed circuit?

A closed circuit is a circuit that has something that gives energy(batteries) and that has an energy user.

What is an open circuit?

An open circuit is a circuit that doesn’t connect all the way around.

What is an short circuit?

A short circuit is a a circuit that has an energy giver but, not a user

The safest way to use a drill:

The safest way to use a drill is to always have it lined to your shoulder so you have more control over the drill and so it can go straight. If you were right-handed then you would have your left hand on the top of the drill and your right hand on the trigger.

The safest way to use a saw:

The safest way to use a coping saw is to never fight it, just let it do its job.And the different from other saws so it cuts on the way back. And never ever rock it or the blade will break.

The safest way to use a file:

The file is just like the coping saw. Never fight it and always have a clear work space.