Ok I may be young but combine the two reactions to create a compund
<h2>Input =

, water and Output =

</h2>
Explanation:
The light reactions of photosynthesis use water and produce Oxygen, NADPH.
The equation for photosynthesis :
→ 
The process of photosynthesis in two stages -
- The first stage is called the light reaction in which the light energy from the sun is captured and converted into chemical energy stored in the form of ATP and NADPH
- The second stage is the process of conversion of ATP molecules to sugar or glucose (the Calvin Cycle)
For a light reaction -
Net Input is of,
, 
Net Output is of, 
It looks all correct to me, great job!
I will show you a method to find a velocity of anything:-
Find average velocity when acceleration is constant.
Set up an equation with position and time instead.
Find the distance between the start and end points.
Calculate the change in time.
Divide the total displacement by the total time.
Solve problems in two dimensions.