Which of the following constitutes the largest group of steroid users on the high school campus? Male athletes Female athletes Male non-athletes, using for appearance and social purposes Female non-athletes, using for appearance and social purposes

15. give an example for some particles or waves that are moving faster than light in everyday life 16. what is a laser? 17. what is an oscilloscope? 18. what does it means practically that nothing is faster than light in vacuum? 19. what is vacuum?

Carbon-14 is a radioactive element that undergoes beta decay. which force is responsible for allowing carbon-14 to become stable? electromagnetic gravitational weak nuclear strong nuclear

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.