How might solar heat be most efficiently used to generate colder temperatures?
A) This is a trick question and is not possible.
B) Use the solar heat to evaporate water. As the water evaporates, the temperature drops.
C) Use the solar heat to generate electricity, which drives a device that lowers the temperature.
D) Use the solar heat to inflate a balloon. Release the balloon and the temperature of the air escaping the balloon drops.
Question 2
Suggest how solar energy might help eliminate pathogens in drinking water.
A) Exposure of the drinking water to the Sun's ultraviolet rays.
B) Use the solar energy to distill the water.
C) Pass the drinking water through the hot zone of a solar collector.
D) all of the above