Carbonate groups contain a single carbon atom, and three oxygen atoms in a trigonal molecular geometry. The carbon atom has two single bonds to two oxygen atoms and a double bond to the third oxygen atom. Therefore, in addition to carbon, carbonate minerals contain oxygen. An example of a carbonate mineral is calcium carbonate, often found within rocks.
The possibility to answer is C.
Multiply 80 by 12 to get 960 months.
Hope that helps :)
The studies are designed this way b/c it removes the power of suggestion and the double-blind study keeps both researchers and participants in the dark. So this compared to who is receiving the treatment which is relevant b/c it stops the researchers from accidentally overbalancing the study participants, or unintentionally favoring their assessment of the conclusions.
When a scientific experiment is carried out in a controlled setting, all variables are kept the same except for the C. experimental. Experimental variables are the things you are studying in the experiment and it is the only variable you can change.
