In the function b(t) = -0.32t^2 + 27t + 253, 't' is the independent variable that indicates the number of years since 2008. This means that when t = 0, it corresponds to the year 2008, t = 1 corresponds to 2009, and so on. The domain of the function is t >= 0 because time cannot be negative; we only consider the years from 2008 onwards. The range values that would not make sense are any negative values, as a population cannot be less than zero. Therefore, the function must yield non-negative outputs. The graph of this function is continuous because it represents a quadratic equation, which produces a smooth curve without breaks, indicating that the population of bobcats changes gradually over time.