an easier analogy: 100-stories building that stays on 1 cm^2 area has a total surface of 100 cm^2. Now, make the height of this building 1 cm, and you have 100

an easier analogy: 100-stories building that stays on 1 cm^2 area has a total surface of 100 cm^2. Now, make the height of this building 1 cm, and you have 100 cm^2 surface in 1 cm^3 volume. Make it 1M floors, and you are talking about 1M cm^2 = 100 m^2