흥미진진한 이야기들! ② interesting stuffduck's quackintelligent peoplemen and womenpearlscoca-colachicken's flight INTERESTING STUFF! ② ● A duck's quack doesn't echo, and no one knows why. ● Intelligent people have more zinc and copper in their hair. ● Men can read smaller print than women can; women can hear better. ● Pearls melt in vinegar. ● Coca-Cola..