after extensive solo trials, all hyenas were successful in cooperating, displaying remarkable efficiency even on their first try. until 2006, it was the 50 most beautiful people. at the cold end—the water exit from the top pipe, because the cold water entering the bottom pipe is still cold at 20 °c, it can extract the last of the heat from the now-cooled hot water in the top pipe, bringing its temperature down nearly to the level of the cold input fluid (21 °c). her works are experienced in a wide variety of contexts and often connect people and ideas. 