Method means a particular form or procedure for accomplishment or approaching something, especially a systematic or established one.
Answer:I believe that the answer is c
Explanation: photosynthesis gives us oxygen to breath therefore it is helpful to humans
Molecular formula of ascorbic acid is 
Molar mass of ascorbic acid = 
Converting 500.0 mg of ascorbic acid to moles: We use molar mass of ascorbic acid to convert mass to moles.

Converting 500.0 mg of ascorbic acid to molecules: The conversion factor used is 1 mole = 
