Let P(t) be the population (in millions) of a certain city t years after 2015, and suppose that P(t) satises the differential equation P'(t) = 0.04P(t), P(O) = 5. (3) Use the differential equation to determine how fast the population is growing when it reaches 6 million people. (b) Use the differential equation to determine the population size when it is growing at a rate of 500,000 people per year. (c) Find a formula for P(t). O A. Solve 6 = 0.04P(t) for P(t). O B. Evaluate P'(t)=0.04P(6). O C. Solve P'(6) = 0.04P(t) for P(t). O D. Evaluate P'(t)=0.04(6). The population is growing at about D million |:| when it reaches 6 million people. (Type an integer or decimal rounded to two decimal places as needed.) (b) Choose the correct process to nd the population size when it is growing at a rate of 500,000 people per year. 0 A. Evaluate P'(t) = 0.04(0.5). O B. Solve 0.5 = 0.04P(t) for P(t). O C. Solve P'(0.5) =0.04P(t) for P(t). O D. Evaluate P'(t)=0.04P(0.5). The population size is about '1 million : when it is growing at a rate of 500,000 people per year. (Type an integer or decimal rounded to two decimal places as needed.) (c) P(t) = E (Type an expression using t as the variable.)