Water consists of hydrogen and oxygen, and the approximate ratio, by mass, of hydrogen to oxygen is 2:16. Approximately how many grams of oxygen are there in 117 grams of water?
Choices:
A) 100
B) 102
C) 104
D) 106
E) 108
(16/18)*117= 
<gadget id="calculator">(16/18)*117</gadget>
<output>104</output>
104 grams   The answer is 104.
<result>C</result>
Water consists of hydrogen and oxygen, and the approximate ratio, by mass, of hydrogen to oxygen is 2:16. Approximately how many grams of oxygen are there in 117 grams of water?