Answer:
<em>The correct option is D) oxygen</em>
Explanation:
The splitting of the water molecules during the light-dependent reactions results in the production of 2 electrons, two hydrogen ions and the formation of oxygen gas. The electrons released by this process make ATP by a process which is known as chemiosmosis. The hydrogen ions released during the light-dependent reactions are converted into NADPH during the light-independent reactions. Oxygen is the by-product and is released into the air. The oxygen is used up by other organisms of the earth for cellular respiration.
Balanced forces are forces that are equal in force but opposite sides. Mary would need to push on the opposite side of Trey with the same force of 30N. (I provided a photo to visualize)