It takes 15 minutes for the interior temperature of an oven to rise from 20°C to 180°C. A cake is placed in the oven for 25 minutes. When the cake is removed, the oven is turned off. The interior temperature of the oven returns to 20°C after 15 minutes. The oven is then turned on again, 45 minutes later. It takes 10 minutes for the temperature to reach 165°C. Cookies are placed in the oven to bake for 20 minutes. When the cookies are removed, the oven is turned off. The interior temperature of the oven returns to 20°C after 10 minutes. a. Sketch a graph of the scenario. b. Label each section of the graph and explain what each one represents.