<span>to isolate and test single variables</span>
For what subjects? I guess I can try :)
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Cells spend most of their lives, about 78 percent of the time, not dividing in a phase called interphase. During interphase the cells get larger, replicate their chromosomes for cell division, synthesize substances that are essential to cell division, and build materials for growth and development.
Answer: B
Explanation: Traits usually die off when they are unneeded by the organism, or if the trait causes harm to the organism's survival. Through natural selection, over time, the organisms with the best combination of traits for its survival will become the dominating species, and those with weaker traits may not survive long enough to pass off their traits to future offspring.