Acomet's motion around the sun is an example of?

Spend time observing or thinking about events that involve matter and energy. which events can you explain? which events can’t you explain?

Iwill give brainliest if you answer right : )

Ammonia enters the expansion valve of a refrigeration system at a pressure of 10 bar and a temperature of 18oc and exits at 6.0 bar. the refrigerant undergoes a throttling process. determine the temperature, in oc, and the quality of the refrigerant at the exit of the expansion valve.