I think a fossil? Thats my guess.
Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's metabolic activities
C) is correct because light energy is converted into glucose in the process of photosynthesis.Also the air we breath in aka oxygen is exhaled as carbon dioxide which plants convert. into oxygen.Products of photosynthesis are the reactants of cellular resperation.
I think for your distilled water of 1 it would look like 27.8 +/- 5 because you can go 5 above or below your average and 2 would be 27.8 +/- 10 because you can go 2 times below or above your average?
