There are 2 knobs for my kelvinator oven. One controls the temperature. However, I don't know what the other knob is for. It has 5 pictures/symbols. One picture shows one line on the bottom, the next has 2 lines, the next one has 3 triangles and 2 lines underneath, another has 3 triangles, one has the picture of an oven light. I want to bake cookies and cakes and meat. Which setting do I use? The model is KC60WB Kelvinator.