Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Input: Consider Input: Sodium-potassium pumps help nerve cells establish a voltage across their plasma membranes.

Output: Sodium-potassium pumps help nerve cells establish a voltage across their what?


Input: Consider Input: One of the properties of an air mass is that an air mass has similar temperature and moisture properties throughout it.

Output: Which of the following is true regarding the properties of an air mass?


Input: Consider Input: It boils water particles become hot enough to overcome the force of attraction between them, what happens to the water.
Output: When water particles become hot enough to overcome the force of attraction between them, what happens to the water?