I believe that it is the first one: "They are quickly replenished."
Answer:
0.02685 M is the molarity of the barium hydroxide solution.
Explanation:
To calculate the concentration of acid, we use the equation given by neutralization reaction:

where,
are the n-factor, molarity and volume of acid which is 
are the n-factor, molarity and volume of base which is
mm.
We are given:

Putting values in above equation, we get:


0.02685 M is the molarity of the barium hydroxide solution.
I draw a cell to start with and I label it
Answer:
We will derive the combined gas equation from the law of Gases
Boyle's law
P∝1/V
PV=Constant
Charles law
V∝T
Avogadro's Law
V∝n
By combining these three equations we get the combined gas equation
PV=nRT
V=nRT/P
If n=1 mole
V=RT/P
By putting the value of R, T, and P in the above equation we can calculate the volume of the gas at STP.
Answer:
Conducting an experiment
Explanation:
This is because you must test your hypothesis by doing an experiment on the hypothesis