At 20∘C, the hole in an aluminum ring is 2.400 cm in diameter. You need to slip this ring over a steel shaft that has a room-temperature diameter of 2.406 cm. To what common temperature should the ring and the shaft be heated so that the ring will just fit onto the shaft? Coefficients of linear thermal expansion of steel and aluminum are 12×10^-6 K^-1 and 23×10^-6 K^-1 respectively. Express your answer in degrees Celsius to two significant figures.

At 20∘C, the hole in an aluminum ring is 2.400 cm in diameter. You need to slip this ring over a steel shaft that has a room-temperature diameter of 2.406 cm. To what common temperature should the ring and the shaft be heated so that the ring will just fit onto the shaft? Coefficients of linear thermal expansion of steel and aluminum are 12×10^-6 K^-1 and 23×10^-6 K^-1 respectively. Express your answer in degrees Celsius to two significant figures.