Answer:
Oxygen
Explanation:
The formula for cellular respiration is oxygen + glucose -> water, carbon dioxide, energy. You can already cross out A and D because they aren't in the formula, so you have two left, water and oxygen. The reason why it is oxygen and not water is because without oxygen you can't even have water. also, I just got this right on my test :-)
It’s called a solar system because solar means “relating to or determined by the sun” and system means “a set of things working together as parts of a mechanism or an interconnecting network” and the solar system is a whole bunch of planets and other things that are related to the sun and working together.
CCAGAT , or B.
The reason why is because A only pairs with T, and G only pairs with C. So, if you have a strand with GGTCTA, the only possible pairing for that to replicate is CCAGAT.