[问答题]
The graph shows the effect
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1.1.Describe the trend shown in the graph.
1.2.Outline one reason that percentage change was used rather than change in length.
2.1.State two variables that would need to be controlled in this experiment.
2.2.Explain why it is important that one of the factors you chose in (i) needs to be controlled in this experiment.
3.1.Explain how auxins such as IAA promote shoot growth.
3.2.Deduce, with a reason, which concentration of IAA should be used to grow sesame seed plants.
