Troposphere because it is at the very top. As u delve deeper, you get to the core which is the hottest part of the earth
photosynthesis produces oxygen and glucose as the end products whereby the glucose is used as food by plants and oxygen as a byproduct.
cellular respiration produces water and carbon dioxide and the end products and by products where by energy is stored
The combined mass of rock 1 and 2 = 19.28 + 25.3
= 44.58
Difference between rock 3 and combined rocks
= 46.3 - 44.58
= 1.72 grams
therefore, the third rock was 1.72 grams greater than the combined mass of the other two rocks.