Question: Fact 1: Temperature changing can cause phase changes. Fact 2: Melting is the change of phase from a solid to a liquid. Given the two facts above, what can cause melting?
OPTIONS:
- Changing pressure
- Heat energy
- Water expanding
- Evaporation
- converting electricity to heat
- Increase in mass
- Temperature changing
- Chemical reaction
Answer: Temperature changing

Question: Fact 1: The vanes rotating in an electric fan causes air to move. Fact 2: Air is a gas, and air has pressure. Given the two facts above, the vanes rotating in an electric fan cause what to move?
OPTIONS:
- energy
- waves
- wind
- cars
- storms
- homes
- Lift
- gases
Answer: gases

Question: Fact 1: Ablack hole is formed by a high-mass star collapses. Fact 2: Then, gravity collapses the star. Given the two facts above, what is the initial cause of black holes?
OPTIONS:
- energy
- gravity
- heat
- photons
- mechanical
- sun's heat
- cracking
- Smoking
Answer:
gravity