A circle doesnt have a sides so 0
Answer:

The world population at the beginning of 2019 will be of 7.45 billion people.
Step-by-step explanation:
The world population can be modeled by the following equation.

In which Q(t) is the population in t years after 1980, in billions, Q(0) is the initial population and r is the growth rate.
The world population at the beginning of 1980 was 4.5 billion. Assuming that the population continued to grow at the rate of approximately 1.3%/year.
This means that 
So


What will the world population be at the beginning of 2019 ?
2019 - 1980 = 39. So this is Q(39).


The world population at the beginning of 2019 will be of 7.45 billion people.
Row A: x = 3
y = 2x - 3
y = 2(3) - 3 = 3 This is correct
Row B: x = 5
y = 2x - 3
y = 2(5) - 3 = 7 This is correct
Row C: x = 7
y = 2x - 3
y = 2(7) - 3 = 11 this is correct
Row D: x = 10
y = 2x - 3
y = 2(10) - 3 = 17 THIS IS INCORRECT, SO ROW D