100%-9%=91%
$819/91%=$900
100%+5%=105%
$900x105%=$945
Answer: He should sell it at $945 to make a profit of 5%.
        
             
        
        
        
Answer:
brown hair or black hair.
 
        
                    
             
        
        
        
The scientific law of one organism feeding off other where energy is transferred from one form to another is known as the law of conservation of energy.
<h3>How the sun is the primary source of energy for ecosystems?</h3>
Energy from the highest energy source that is sun is absorbed by plants to convert it into food (i.e a form of energy). plants are the only ones that can convert sunlight into another form of energy directly.
The animals and organisms that feed off of the plants take some part of this energy for their life cycles and then the animals that feed off of these animals again take some part of this energy and carry on with their life cycle, this is how energy from sun (highest source) is transferred to different organisms by Just changing form.
Thus, The scientific law of one organism feeding off other where energy is transferred.
To learn more about primary source of energy click here: 
brainly.com/question/20893934
 
        
             
        
        
        
The mitochondria converts food into energy
        
             
        
        
        
Answer:
A Elements
Explanation:
Elements are pure substances that cannot be broken down into simpler substances by ordinary chemical means.