Think of it this way:
DNA inside cells store all the genetic information on a person's looks, eye colour, hair colour etc. It makes them unique. The analogy of being like books in a library basically suggests that in a library there is so much information and every book is different with different knowledge... That's basically what DNA is; millions of different information things. 
        
             
        
        
        
A vigorous excersie that requires a lot of energy
        
             
        
        
        
Answer:
Chromosomes are made up of  DNA(deoxyribosenucleicacid) which is a protein complex called chromatin that is organized into subunits called nucleosomes. The way in which eukaryotes compact and arrange their chromatin also helps regulate gene expression.
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Answer:
The air is full of water, as water vapor, even if you can't see it. Condensation is the process of water vapor turning back into liquid water, with the best example being those big, fluffy clouds floating over your head. And when the water droplets in clouds combine, they become heavy enough to form raindrops to rain down onto your head.
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Answer:
the answer is C
Explanation:
The Universal Transverse Mercator coordinate system is a global system of grid-based mapping references