Q: The first reported nuclear fission occurred in 1939 when three german scientists bombarded uranium-235 atoms with slow-moving what? Choices: - protons - electrons - isotopes - neutrons A:
neutrons

Q: What kinds of waves are composed of various oscillating electric and magnetic fields? Choices: - elastic - seismic - tidal - electromagnetic A:
electromagnetic

Q: What flexible organ enables swallowing and speech? Choices: - large intestine - stomach - diaphram - tongue A:
tongue

Q: The skull is a part of a vertebrate endoskeleton that encloses and protects what organ? Choices: - nervous system - lung - heart - brain A:
brain