You require a sheet of copper for a home project, and since it is sold by the square foot, you buy 2.0 ft2 (according to the label). But, when you get home and check the actual dimensions for yourself, you find that the area is really 1.997 ft2. If you gauged the area when it was 20°C, what must the original temperature has been when the sheet was cut and the label attached? (In °C)