I need answer to resolve this problem step by step

World population: The table lists actual and projected World population p in billions for selected years t.

 

 

t 1974 1987 1999 2012

p 4       5       6      7

 

 

(a) Find the slope of each line segment connecting

Consecutive data points in the table. Can these

Data be modeled with a line? Explain.

 

(b) Does the polynomial 0.077t – 148 give good

Estimates for the world population in year t?

Explain how you decided.