Robin spent one hour and 50 minutes cleaning is her room if it was 645 when she finished what time was it when she start?

Which rational number could be graphed between -4 and -5

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.

Math it's appreciated. (picture provided)