A truck driver is attempting to deliver some furniture. First , he travels 8 km east, and then he turns around and travels 3 km west. Finally, he turns again and travels 12 km east to his destination. a- what distance has the driver traveled? b- what is the drivers total displacement?

Which of the following correctly describes what happens when an atomic bomb explodes? small pieces of fissionable material are joined and form a body with a mass greater than the critical mass, the relative number of neutrons escaping decreases, and a chain reaction and explosion result. large pieces of fissionable matter are brought together quickly and form a body with a mass smaller than the critical mass, the relative number of escaping neutrons increases, and a chain reaction and explosion result.