b) Find the annual rate of interest (as a %) if the amount is $15'840 after 5 years for a principal of $12'000. [3] (6 Marks) # 10. The population of Hazlewood in 1990 is 32'000. The population increases exponentially at 9% per year. Using 1990 as the base year a) Write the exponential model for the population P, after t years. [1] b) Find the population, to the nearest hundred, in 1996. [2] c) In which year does the population first exceed 80'000. [3]