2). Consider the following scenario and question: A firefighter stood on the middle rung of a ladder. When the smoke became less thick, the firefighter moved up 4 rungs. Then it got too hot, and the firefighter moved down 6 rungs. Later, the firefighter went up 7 rungs and stayed there till the fire was out. After the fire was out, the firefighter climbed the remaining 4 rungs and entered the building. How many rungs does the ladder have? Your goal is to answer the question using Polya's Four Step Problem Solving process. Consider each steps and write down all of your work and/or explanation needed. Make your writing and your work complete and clear enough that someone could follow your process just by reading what you've written. Step 1: Understand the Problem. Step 2: Devise a Pan. Step 3: Carry out the plan and solve the problem. Step 4: Look back and check the answer. Please write your final answer in a complete sentence below: