Red light bends the least when it is refracted by a prism. Red light has the longest wavelength and bends the least when refracted by a prism. Violet light bends the most and has the shortest wavelength.
A planet is round because of gravity. A planet's gravity pulls equally from all sides. Gravity pulls from the centre to the edges like the spokes of a bicycle wheel. This makes the overall shape of a planet a sphere, which is a three -dimensional circle