The fluid filled area between the pleural layers is called the pleural cavity.
<h2>Answer:</h2>
pOH = 4.6
<h2>Explanations:</h2>
The sum of pH and pOH of a solution is 14as shown:

Given the following parameter
pH = 9.4
Substitute the given parameters into the formula to have:

Hence the pOH of the solution of pH of 9.4 is 4.6