Question

according to the passage, what is the most important reason for controlling variables in a fair test? a)to ensure that the results are due to the independent variable alone. b. to use more materials. c. to make the experiment take less time. d. to make the experiment easier to conduct. in an experiment to determine if different types of fertilizer affect plant growth, which of the following would be the independent variable? a. the amount of water given to each plant. b. the height of the plants. cthe type of fertilizer. d. the type of soil used. what does the passage suggest is a benefit of finding failure points during testing? a. they prove that the initial hypothesis was correct. b. they indicate that the experiment was not a fair test. c. they always lead to unexpected results. dthey help us see what we can improve. according to the passage, why is it important to only change one variable (independent variable) in a fair test? a. to ensure that any observed changes are due to the variable being tested. b to save time and resources during the experiment. c to make it easier to graph the data. d to make the experiment more complex and interesting. in the context of fair tests, what is the role of controlled variables? a. to intentionally introduce changes to observe their effects. b. to identify potential failure points in the experiment. c to measure the changes that occur as a result of the independent variable. d. to ensure that only the independent variable affects the dependent variable.

Explanation:

1. In a fair - test, controlling variables ensures results are due to the independent variable only. This eliminates the influence of other factors.
2. In an experiment on fertilizer and plant growth, the type of fertilizer is what is being changed (independent variable), while other factors like water amount, plant height, and soil type are either controlled or are dependent variables.
3. Failure points in testing help identify areas for improvement. They don't prove the hypothesis right or wrong about the fairness of the test directly, but offer insights for betterment.
4. Changing only one variable in a fair - test ensures that any observed changes are due to that variable being tested, which is crucial for accurate results.
5. Controlled variables in fair - tests are held constant to ensure that only the independent variable affects the dependent variable.

Answer:

1. A. To ensure that the results are due to the independent variable alone.
2. C. The type of fertilizer.
3. D. They help us see what we can improve.
4. A. To ensure that any observed changes are due to the variable being tested.
5. D. To ensure that only the independent variable affects the dependent variable.