lift-the-flap questions and answers how does it work?

Lift-the-flap Questions And Answers How Does It Work?

This excellent addition to the ever popular Questions \x26 Answers series lifts the flap on all kinds of gadgets, systems and ideas. It answers questions such as How does electricity get into our walls? Why do waves go up and down? and Where does money come from? Perfect for every inquisitive child.