Solved by a verified expert:1. Blood doping (using injected substances to artificially enhance performance) is illegal in many sports. Two substances used are erythropoietin and hypoxia-inducible factors (HIF). One of the actions of HIF is to increase formation of new blood vessels (angiogenesis). Explain how administering erythropoietin can increase performance and how HIF can increase performance through angiogenesis.2. Myoglobin levels are higher in Tibetans and other ethnic groups that live at high altitudes. Explain the benefit of higher myoglobin levels for individuals living at high altitudes.