Select all the correct answers. let f(t) be the amount of garbage, in tons, produced by a city, and let t be the time in years after 2000. which statements are true for the given function? the dependent variable is f(t). when f(12) = 2,155, the 12 represents "12 tons of garbage produced," and the 2,155 represents "the year 2155." when f(4) = 1,458.6, the 4 represents "the year 2004," and the 1,458.6 represents "1,458.6 tons of garbage produced." the dependent variable is t. when f(2) = 1,323, the 2 represents "the year 2002," and the 1,323 represents "1,323 tons of garbage produced." the independent variable is t. the independent variable is f(t).