A car is driven a distance of 8.7 km east, then 4.1 km in a direction 35◦ north of east. Then the car is driven 7.2 km in a direction 25° south of west. Relative to the starting point, the final location of the car is .

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.