Mrs. jordan measures 18 grams of water into a beaker. if she doubles the amount of water that she puts into the beaker, how will the proportions by mass of hydrogen and oxygen in the water be affected?

Based on the law of definite proportion, a chemical compound is always made of the same proportion of elements by mass irrespective of the method in which it is prepared.

The chemical formula for water is H₂O i.e. 2 units of H combines with 1 unit of O. Thus the ratio by mass of H:O is 2:16. This ratio will remain unchanged even if the amount of water is double from 18 g to 26 g.

it's c (engineer's do their work with mechanical stuff not on any living being)