Below are the choices:
<span>The independent variable is the number of dry cells, and the dependent variable is the length of time the bulb works.
</span><span>The independent variable is the length of time the bulb works, and the dependent variable is the number of dry cells.
</span><span>The independent variable is the number of dry cells, and the dependent variable is the amount of energy available.
</span><span>The independent variable is the amount of energy available, and the dependent variable is the number of dry cells.
</span>
I think the answer is <span>The independent variable is the number of dry cells, and the dependent variable is the amount of energy available.</span>
        
                    
             
        
        
        
Animal fibers are fibers from animals and consist mainly of protein. They contain not only silk fiber from silkworms and fur fiber from sheep wool but also collagen fiber extracted from animal skins, chitin from crustaceans, and shellfish like shrimp and chitosan made by deacetylating chitin.
        
                    
             
        
        
        
Scientists can measure the height in
different units but problem could arise when they compare all the measurements.
That is the reason there is standard units for measurements.
<span>There may be error arises when an
American scientist is measuring the height of an object in inches and other Australian
scientist is measuring the height of same object in meters. Their data cannot
be compared because they are using different units to measure height.</span>
 
        
             
        
        
        
Answer: 
In order  to determine unequivocally which of the peaks represent Aldrin, I would run the pure sample through the chromatography equipment.
Explanation:
Gas chromatography is a technique that separates molecules based on their volatility and interaction with both the stationary phase. 
The peaks on the chromatogram show how long a substance took to leave the column. Since each different substance substance will leave the column at a different time, each peak can be attributed to a substance. 
Therefore, to know which of the 6 peaks represent Aldrin, it is necessary to run the pure Aldrin in the chromatography equipment and see the time of the peak. Then you just need to compare both chromatograms and indentify Aldrin.