A class has 10 students with ages 3 3 3 3 3 4 4 4 4 5. If a student is chosen randomly, the probability of the student being age 3 is 5/10 or 0.5, age 4 is 4/10 or 0.4, and age 5 is 1/10 or 0.1. What is the expected age of a randomly chosen student?

The american academy of pediatrics wants to conduct a survey of recently graduated family practitioners to assess why they did not choose pediatrics for their specialization. provide a definition of the population, suggest a sampling frame, and indicate the appropriate sampling unit.