Which of the following solutions should be chosen to restore an ecosystem naturally? a. reintroducing an animal to the ecosystem b. preserving land in the ecosystem c. moving predators out of the ecosystem d. moving prey out of the ecosystem

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.

Why do astronauts in the space shuttle weigh less?

Use 4 to 5 complete sentences, explain the concepts of beats and how beats are produces.