Which of these systems of equations would be best solved using the subtraction​ method? I. 2x−7y+3y = 4
−6x−4y = −52
II. 2y = −5x+6x−5
y = 2x−6
III. −7x+3x+2y = 4
4x−6y = −52

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.