The mass of
is 0.185 g.
To calculate the number of moles first calculate the molar mass of
.

Molar mass of nitrogen and oxygen is 14 g/mol and 16 g/mol respectively
Thus, 
Now, number of moles can be calculated from mass and molar mass as follows:

Therefore, number of moles of 0.185 g
is 0.0042 mol.
Answer: b- it is always a substance
Explanation: matter can be any liquid, gas, or solid that takes up space so the answer cannot be C or D. For answer number A to be true, you would have to remove the word more, because matter just has mass and takes up space it does not have "more mass"
Answer: I say it is A sorry if I'm incorrect
Explanation:
Maybe this example could help you to understand this problem.
https://image.slidesharecdn.com/121howmanyatoms-091201144624-phpapp02/95/12-1-how-many-atoms-17-728....