Use a calculator with a y key or a A key to solve the following. The exponential function f(x)=544(1.026)* models the population of a country, f(x), in millions, x years after 1975. Complete parts (a) -(e). a. Substitute 0 for x and, without using a calculator, find the country's population in 1975. The country's population in 1975 was 544 million. b. Substitute 27 for x and use your calculator to find the country's population, to the nearest million, in the year 2002 as modeled by this function. The country's population in 2002 was 1088 million. c. Find the country's population, to the nearest million, in the year 2029 as predicted by this function. The country's population in 2029 will be 2175 million. d. Find the country's population, to the nearest million, in the year 2056 as predicted by this function. The country's population in 2056 will be million.