On the pH scale ranging from 1 to 14, 7 is neutral. Any number greater than 7 is alkaline; any number lower than 7 is acidic. With that in mind, in turns out that the oceans are serving as a carbon sink. About __________ percent of current carbon dioxide emissions have been absorbed into the oceans.
A. 30
B. 40
C. 50
D. 60
Ans : C
1 answer