The most commonly reported symptom of withdrawal from caffeine is __________

Ted's pediatrician has prescribed Ritalin for the fourth-grader. Which of the following is the most likely prescribed dosage regime?

a. Ted will take a single dose every morning before school. b. Ted will take one dose each day when he feels the need to concentrate. c. Ted will take one dose per week throughout the year and into his adolescent years. d. Ted will take one dose in the morning and another at lunchtime, with a possible third dose after school.

When compared to other methods, an advantage of experiments is that the participants are always representative of the larger population

Indicate whether this statement is true or false.