Explanation:According to the law of definite proportions or constant composition, in all the pure samples of a particular chemical compound, the constituent elements are generally combined in the same proportions by mass.

The combination is regardless of the mode or origin of the of the compound.

A sample of pure water,whatever the source will be, will always contain 88.8% by mass of oxygen and 11.1% as the mass of hydrogen.Both the gases are divided in a constant ratio. Since, H2O contains the elements H and O in a fixed ratio by mass, this explains the law of constant composition, thus they are divided in a ratio of 1:8.Thus, the mass of Oxygen is 88.8%.

option a is the right answer

option a is the right answer

option a is the right

option a is the right answer

88.8% is the percent of mass of oxygen

a)88.8 is the right answer......

88.8% mass of oxygen and 11.1% by mass of hydrogen

88.8 is the right answer....

option A is a correct answer

Option a is correct answer

88.8% is percentage of oxygen

88.8 percent of all the water we drink today contains oxygen

88.8% of oxygen in this water sample

A is the correct answer

a sample of pure water, whatever the source always contain (a)88.8% by mass of oxygen and 11.1%by mass of hydrogen.

a 88.8 is correct answer