it is important to know the different between atoms, ions, and isotopes. Choose all of the correct answer.

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.

What happens when a rubber rod is rubbed with a piece of fur?

Select all the correct answers. which three statements about electromagnetic radiation are true?