Final answer:
No, it would not be plausible to estimate that 59% of the general public is caffeine dependent based on a study with a sample size of 120 people.
Step-by-step explanation:
No, it would not be plausible to estimate that 59% of the general public is caffeine dependent based on a study with a sample size of 120 people. In order to generalize the results to the general public, a larger and more representative sample would be needed. The sample size should adequately reflect the diversity and size of the population being studied.