The corrrect option is D.
Since the scientist was trying to determine if substance A affect the rate of reaction of X and Y, the best thing to do is to make substance X and Y to react together first, he should then measure the time taken for the reaction to take place. Next, he should make X and Y to react together again, but this time in the presence of A. The time taken for the reaction to occur should be measures. The scientist can now compared the two time measurements and decide if there are difference between them or not.
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Answer:
In the human body, amylase is predominantly produced by the salivary glands and the pancreas.
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It tells the audience if the results support or contradict the hypothesis
Explanation:
When a scientist describes the materials that she used and how she performed her experiments, it tells the audience if the results supports or contradicts the hypothesis.
- A hypothesis formulation helps to test a scientific claims.
- Experiments are usually hinged on well designed hypothesis.
- From the hypothesis, one can be sure the experiment is tuned and designed within the scope of the observation desired to be tested.
- This is why the materials used and procedures followed in an experiment can tell if the results supports or contradicts the hypothesis.
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Experiment brainly.com/question/5096428
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