Question

question 31
the epithelium of parietal pleura of the lung is simple, which means:
not hard.
not complicated.
one layer.
more than one layer.
question 32
what is the purpose of the arm in a microscope?
a person holds the arm when moving the microscope.
light passes through the arm before reaching the objective
the adjustment knobs are located on the arm

Explanation:

For Question 31: In anatomical terminology, "simple" when describing epithelium refers to a single layer of cells.
For Question 32: The arm of a microscope is the structural part that users grip to safely move and transport the microscope, while light paths and adjustment knobs are not its primary defining purpose.

Answer:

Question 31: One layer.
Question 32: A person holds the arm when moving the microscope.