D. <span>controlled
is the right answer because a</span><span>n </span>experiment<span> in which an observer tests a hypothesis by looking for changes carried by alterations to a variable.</span>
Answer:
Your answer would be ( A star has 2 star systems )
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Prophase is the first step in mitosis and many changes occur. Chromatin fibers become coiled into chromosomes, with each chromosome having 2 chromatids joined at a centromere. The mitosis spindle, composed of microtubules and proteins, form in the cytoplasm.
Carried on the X or Y chromosomes
