Ask Your Teacher The world population in 2016 was estimated to be 7.4 billion people, and it is increasing by about 1.1% per year. Assume that this percentage growth rate remains constant through 2030. Explain why the population is an exponential function of time. Population is an exponential function of time because the population is always growing. Population is an exponential function of time because the population is always shrinking. Population is an exponential function of time because the population growth rate is always −1. Population is an exponential function of time because the percentage growth rate is constant. Population is an exponential function of time because the percentage growth rate is always 1. Correct: Your answer is correct. What would you expect the world population to be in 2030 (in billions of people)? (Round your answer to one decimal place.) 8.3 Incorrect: Your answer is incorrect. billion people