Answer
• a) Discrite.
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• b) Discrete.
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• c) Continuous.
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• d) Continuous.
Step-by-step explanation
• Discrete variables,: countable values, you should always be able to count the values of this type of variables.
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• Continuous variables,: can take on any value within a range, infinite number of possible values within a range.
Based on the latter:
• The number of fellow classmates can be counted.
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• The number of defective compact disc can also be counted.
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• However, the body weight can take a value within a range.
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• Similarily, the reaction time study can take different values within a range.