Scenario: Does amount of caffeine affect memory? This study was conducted using 30 participants who report not regularly consuming caffeine. The researcher has those 30 participants complete a memory task on three separate days (counterbalanced among participants). All participants complete the memory task after having none, moderate, and high levels of caffeine. The memory task was quantified as number of items correctly recalled. Assume data meets all assumptions for a parametric test. Question: What is the scale of measurement of the dependent variable in this scenario?