3. The architect Alexander Muir is designing a house for the interdimensional being Max Preetorius. To study the design, Alexander builds a simple model out of wire and paper. The lower floor of the house is a cube of side length a centimeters (cm). The upper floor of the house is a cube of side length b cm. The upper floor is attached to the center of the top face of the lower floor. For structural integrity, Alexander will choose 0