Core concepts
Experiment / Case study
Three children and three books
Exercises
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Worked example
Example
Solution steps
- 1
- 2
Answer
Worked example
Example
Solution steps
- 1
- 2
Answer
Worked example
Example
Solution steps
- 1
- 2
Answer
Practice set
Answered 0 / 6
1Fill in the blank
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2Fill in the blank
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3Fill in the blank
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4True / False
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5True / False
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6True / False
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