When examining indentations, document examiners may apply ash <span>to help reveal the indentations</span>
        
                    
             
        
        
        
D is the correct answer ur welcome
        
                    
             
        
        
        
Certain elements are required in large quantities, and others are required in small amounts by the body, but both are essential for the survival of the cells. The cells which are required in large amounts are called as macronutrients, while the ones required in small quantities are called as micronutrients, or trace elements.
Hence, the answer is trace elements or micronutrients.
 
        
             
        
        
        
Answer:
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A.
<u>The ribcage expands to allow air to enter the lungs</u> is an example of the skeletal system interacting directly with the respiratory system.
Explanation:
The skeletal system is mainly made up of bones - like the ribcage in this case - while the respiratory system is made up of the lungs, trachea, diaphragm, etc.  
When inhaling, the diaphragm contracts, therefore increasing the volume of the chest cavity. The muscles between the ribs also contract causing the ribcage to stretch upwards and outwards. This also contributes to an increase in the volume of chest cavity. Consequently, the pressure in the chest, decreases causing atmospheric pressure to rush  air into the lungs. 
When these muscles contract, they raise the pressure in the chest cavity causing air to rush out of the lungs. 
Learn More:
For more on interaction of the skeletal system and the respiratory system check out;
brainly.com/question/13947489
brainly.com/question/2756469
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