answer: 
by having a high genetic level of melanin in your skin, you're skin is more protected from the ultra violet sun rays. Darker skinned races have more melanin present, these races originate from hot countries where sunlight is often present; the production of melanin in their skin allows them to reflect and inhibits they're skin from becoming extremely damaged. Light skinned races don't have a large amount of melanin due to they're native countries lacking sunlight. This is an evolutionary adaptation of the human race.
 
        
                    
             
        
        
        
<span>The atmosphere of Venus is mostly carbon dioxide, 96.5% by volume. Most of the remaining 3.5% is nitrogen. Early evidence pointed to the sulfuric acid content in theatmosphere, but we now know that that is a rather minor constituent of theatmosphere. 
T</span>he atmosphere of Neptune consists mainly of hydrogen and helium, but about 2.5-3% of the atmosphere is methane. Like Uranus, clouds in Neptune's atmosphere<span> are composed of crystals of methane.</span>
        
                    
             
        
        
        
Answer: the answer is A 
Explanation: i just did it
 
        
             
        
        
        
Multiply by the power of the eyepiece, usually 10x.
        
             
        
        
        
An electrocardiogram (ECG) provides information about B) the rhythm of heart contractions 
The rhythm of heart contractions can be known by an electrocardiogram (ECG).
An ECG or Electrocardiogram is a method to diagnose the heart conditions to check the normal functioning of the heart.
The process to measure the electrical signals of the heart can be done by using this machine.
In this technique, three leads are attached to both the wrist and the left ankle to measure the electrical activity of Heart. The rhythm of the heart contraction and relaxation can be used to find out any heart abnormality.
It is used to investigate the heart problems associated due to bad health or some chronic inflammation affecting the functioning the body. Shortness of breath or nausea is investigated by using an ECG machine to help the patient and doctor to find out the cause.
It consists of QRS complex which measures the heart beat.
Learn more about Heart here, brainly.com/question/16566688
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