1. We are given the surface area of a piece of paper as 552 cm² and need to convert this area into mm². 2. Recall the conversion factor: 10 mm = 1 cm. 3. Since area is two-dimensional, we square the conversion factor: $$(10\text{ mm})^2 = (1\text{ cm})^2$$ which implies $$100\text{ mm}^2 = 1\text{ cm}^2$$. 4. To convert 552 cm² to mm², multiply 552 by 100: $$552 \times 100 = 55200$$ 5. Therefore, the area of the paper in mm² is $55200$.