Answer:
Volume, 
Explanation:
Given that,
The diameter of a human cell is 11 μm
It is enclosed by a membrane that is 4,4 nm thick.
We need to find the volume of the cell. The cell is spherical in shape. The volume of a sphere is given by the formula as follows :
r is the radius of the sphere, r = 5.5 μm
So,
So, the volume of the cell is 
.
The chemical formular for water is H2O.
The H aspect of the formula stands for hydrogen gas and the subscript 2 which is attached to the H symbol signifies that two atoms of hydrogen are joined together, that is two atom of hydrogen are present.
The chemical formula of water indicates that, two atom of hydrogen react with one atom of oxygen to form one molecule of water.
In chemical formulae, subscripts are normally used to indicate the number of atoms that are present in a molecule.
