Help pls i'm so behind

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.

The cost of using a service is $0.25 per min. what equation correctly represents the total cost c, in dollars, for d days of use?

What is the area of the shaded sector?