The examples of positive feedback loops are as follows:
- contractions during the process of giving birth
- Blood clotting
<h3>WHAT IS POSITIVE FEEDBACK LOOP:</h3>
- Positive feedback loop is that in which a change in a given direction causes additional change in that same direction. 
- The contractions during the process of giving birth is an example of positive feedback loop because the contractions further stretch the walls and continues until birthing occurs. 
- Also, the clotting of blood causes the stoppage of blood flow. 
Therefore, the examples of positive feedback loops are as follows:
- contractions during the process of giving birth
- Blood clotting
Learn more about positive feedback loops at: brainly.com/question/11312580
 
        
             
        
        
        
The hydrocarbons' surface.
Because the covalent link that exists between hydrocarbon surfaces is different from the surfaces to which the salamander can cling, the salamander has difficulties adhering to these surfaces.
The hydrogen bond is the bond that exists between hydrogen and a bigger molecule like nitrogen or oxygen, whereas a covalent bond includes sharing electrons.
<h3>What Are Hydrocarbons and What Do They Do?</h3>
Crude oil, natural gas, and coal are all examples of hydrocarbons, which are organic compounds made of hydrogen and carbon. The world's primary energy source and a highly flammable substance, hydrocarbons. Petrol, jet fuel, propane, kerosene, and diesel are only a few of its uses.
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Answer: <u><em>D. An observation that has a number associated with it</em></u>
Explanation: The answer is D. An observation that has a number associated with it. I would explain further, but it is pretty self explanatory. 
<em>Good luck!</em>
 
        
             
        
        
        
Answer:
A secret. When you have a secret, you want to tell other people, but when you do, it's no longer a secret.