A technique for measuring cardiac output depends on the concentration of a dye after a known amount is injected into a vein near the heart. In a normal heart, the concentration of the dye at time t (in seconds) is given by the function g(t) = -0.006t⁴ + 0.140t³ - 0.053t² + 1.79t.

(a) Graph g(t) on [0, 6] by [0, 20].

(b) In your graph from part (a), notice that the function initially increases. Considering the form of g(t), do you think it can keep increasing forever? Explain.