A social scientist used research on the smartphone usage of teenagers in the United States for the years 2011 to 2019 to determine the function

P(z) = 5.6x + 40.3. The graph of the function is shown where a represents the number of years since 2011 and P represents the percentage

of US teenagers who own a smartphone.

Part A: Determine the constraints of the domain for P (2).

Part B: Identify the range based upon the constraints from Part A.