Answer:
A
Explanation:
Sorry if I made an mistake on the answer
 
        
             
        
        
        
Answer:
D. blue-violet and red-orange
Explanation:
The light reactions of photosynthesis use only  certain wavelengths of visible light. 
Light absorbing molecules known as pigments in  the membranes of a granum absorb mainly  in blue-violet and red-orange wavelengths. We do not see these absorbed wavelengths. What we see when we look at a leaf are the  green wavelengths that the pigments transmit and reflect.
 
        
             
        
        
        
Answer:
a temporary oxygen shortage in the body tissues arising from exercise.
 
        
             
        
        
        
Hey There!
Here is your answer:
Your answer is that a experiments should be controlled because the experiment could go out of control which could harm or hurt someone.
Also the definition of a controlled experiment is a part of the experiment that's not touched.
Ex: Water is your controlled experiment that's because our not doing anything to the water.
If you need anymore help just ask me!
Hope this helps!
        
             
        
        
        
Answer:
can you give me more information