Scientists from NASA discovered a Nebula with doubled the mass as the Nebula from which our Solar System formed. Explain the similarities and differences between the Solar System that will form from that Nebula and our Solar System. (Note: your response must include a discussion of gravity.)

At 20∘c, the hole in an aluminum ring is 2.800 cm in diameter. you need to slip this ring over a steel shaft that has a room-temperature diameter of 2.804 cm . 1. 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 and23×10−6 k−1 respectively.