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Answer:</h2>
<u>Negative Feedback</u> occurs the the response serves to counteract the stimulus.
A change in which no new substance is formed is called a physical change.
Examples: Crushing a can, Melting an ice cube, Boiling water, Breaking glass, Dissolving sugar in water, Shredding paper, and Chopping wood.
All of these examples may involve a change in shape, form, or appearance, but it DOES NOT involve a change in the molecule structure.
Answer:
Hello!
Primary consumers and producers are two examples of <u>trophic</u> levels, a way to classify living organisms based on their source of nutrients.
Hope this helps!