The correct question is as follows:
How do you convert from grams to moles of a substance
1. Divide by the molar mass
2. Subtract the molar mass
3. Add the molar mass
4. Multiple by the molar mass
Answer: In order to convert from grams to moles of a substance divide by the molar mass.
Explanation:
The number of moles of a substance is the mass of substance in grams divided by its molar mass.
The formula to calculate moles is as follows.

This means that grams are converted to moles when grams is divided by molar mass.
Thus, we can conclude that in order to convert from grams to moles of a substance divide by the molar mass.
These are called subscript number.
That is the number below the normal line of test are called subscript number.
This number indicate the indicate the number of atoms of the element present in the chemical formula.
In both of these C₆H₁₂O₆ and H₂O, the number written below the line of the text are called subscript numbers.
The two dimensions of aluminum foil are given 13.72 cm and 8.63 cm respectively with mass 3.1 g.
The density of aluminum is
. It is defined as mass per unit volume thus, volume of aluminum can be calculated as follows:

Putting the values.

The volume of cuboid is
, the length and breadth are given, height can be calculated as follows;

Putting the values,

Or, approximately 9.7\times 10^{-3}cm
Therefore, thickness of aluminum foil is 
I think the answer is ( A and C ) why I picked a and c it’s because a and c look the same answer. I hope it helped you