Let me compare the growth of the three plants by measuring the sizes of their leaves.
A week later
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opaque box
Reading to Learn
Science for You How did early scientists use more objective methods to do tests? Read ‘The Pioneer of Medical Testing — James Lind’ to find out! Appendix 2
There are small holes at the bottom of the box to let air in.
Plant C
Reflection 3. Do you think this test is fair? Is there room for improvement? Discuss your ideas with your classmates.
The Road to Science
Which scientific questions cannot be answered through fair tests?
Fair testing allows us to find out accurately how a factor affects another variable .
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