30 points! Practice making careful observations. Choose something living to observe, either outdoors or indoors. If you’re observing your puppy playing in your backyard, you must not only record the puppy’s actions but the time of day, the weather, the sounds around you, who else is there, etc. All of these things are important, and should anything surprising happen, it becomes very helpful to have all the information.

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.