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Addiction, dependence and tolerance


A scientist is testing the effects of heroin on monkeys. The table below lists the details of drug treatment on 4 different monkeys.
DetailsMonkey 1Monkey 2Monkey 3Monkey 4
Number of doses delivered per day5310
After a few days, the scientist tests the tolerance levels of each monkey to heroin. She delivers 2 doses of heroin to each monkey and tests their responses.
Which of the 4 monkeys will respond to this test?
Choose 2 answers: