题目

Few in the West seemed to notice when the International Olympic Committee(lOC) decided to award the 2014 Winter Games to the Russian town of Sochi. Yet this choice is full of geopolitical meaning. President Vladimir Putin flew to Guatemala City to address IOC delegates before they voted, and surprised them by speaking in French and for the first time ever in public­-----English. Later he declared that Sochi’s victory was not only a recognition of Russia’s achievements in sports but also an assessment of our country. Sochi, located between the Caucasus and the Black Sea, has poor roads, on如图，将△ABC绕点A逆时针旋转的到△ADE，点C和点E是对应点，若∠CAE=90°，AB=1，则BD=_________．