For Problems 1-2, use the given description of the function f to complete the following: (a) Sketch a graph of the function f. (b) State whether f' is positive or negative. (c) State whether f" is positive or negative. 1. An interest rate f(t) at time t is increasing, and the rate of increase of the interest rate is also increasing. 2. The height f(t) of an object is increasing, but the rate at which the height increases is slowing down. 3. After i weeks, the thickness of the ice layer on the surface of a lake is given by f (t) f(1) cm (see graph to the right). Complete each of the statements with the correct 12 choice(s). Note that there may be multiple correct choices for each item. 10 (a) The thickness of the ice is (positive / negative / increasing / decreasing) (b) The rate of change of the ice thickness is (positive / negative / increasing / decreasing) 2 4 6 8 10 4. For the function below, use algebra to find each of the following limits: b) lim-1-f(x) 3x - 2 051