Tasha Toughgirl is a surfer. Tired of surfing "old school" at beaches with her 2 m surfboard, she decides to surf at her friend's house in a massive lake of gravy. Its viscosity is 100 times that of salt water, and its density is 20% higher than that of salt water. Assume that only the Reynolds number governs the fluid dynamics of surfing and that her board velocity is the same in both situations. What surfboard length would she need to have dynamic similarity between the old school and gravy scenarios