Answer:
a. A hypothesis that does not generate a testable prediction is not useful.
Explanation:
In the scientific method, we generate a hypothesis to explain a phenomenon. After this, it is necessary to create a method to test the hypothesis and make predictions. Moving forward, we test this methodology, generating results and reject or not reject the hypothesis. If the hypothesis can't be tested, the scientific method can't be applied.
The dichotomous key is used as a classifying tool for items in the natural world, (trees, wildflowers, mammals, reptiles, rocks...). At each step of the classification process,<span> the user is given two choices and each choice leads to another question until the item is identified.</span>
<span>A dichotomous key starts with specific information and leads to general information.
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Explanation:
Oxygen does not enter the body except due to some diseases and loss of consciousness, and then the patient uses a ready-made ventilator
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