Given a scientific question and its correct answer, generate supporting facts for the answer. This supporting fact can be an explanation for the answer to the given question.

Example Input: Question: What is a simple machine that consists of a rope wrapped around a grooved wheel? Answer: a pulley
Example Output: A pulley is a simple machine that consists of a rope wrapped around a grooved wheel. Pulleys are generally used to lift a load.

Example Input: Question: Water molecules are polar, so they form what type of bonds? Answer: hydrogen
Example Output: Water molecules are polar, so they form hydrogen bonds. This gives water unique properties, such as a relatively high boiling point, high specific heat, cohesion, adhesion and density.

Example Input: Question: What type of current do generators in cars use? Answer: alternating current
Example Output:
Generators may be set up to produce either alternating or direct current. Generators in cars and most power plants produce alternating current.