Let △A1B1C1∼△A2B2C2 and A2B2A1B1=B2C2B1C1=C2A2C1A1=k. Prove that the ratios of corresponding medians, altitudes, inradii, exradii, circumradii, and distances between corresponding points, such as OH and GH, equal k.
(1) Medians
(2) Altitudes
(3) Inradii
(4) Exradii
(5) Circumradii
(6) Distance between corresponding points (OH, GH, etc.)