1343233 Genocides of the twentieth century killed more people than all the wars. alexmarcelo 325105 Oceans are expected to rise by 50 centimeters by the end of the next century. CM 287952 He studied the scientists considered to be the most significant of the 19th century. CM 244034 The first electric calculator came into existence toward the end of the 19th century. CK 263750 In fact, the sea has already risen 10 centimeters since the beginning of this century. CK 2458017 The United States faced a Bubonic plague epidemic at the beginning of the twentieth century. MethodGT 242145 By the end of the century, the earth will have experienced a dramatic increase in temperature. CK 53860 In Shakespeare's time, in the sixteenth century, tennis was very popular at the English court. CM 2143028 Providing energy to the poor without destroying the planet any further is this century's biggest challenge. Dreamk33 73298 In the late eighteenth century, a passport for an American was usually signed by the President of the United States. CK 1403179 Latin Americans know very little about the history of the indigenous peoples who used to live here several centuries ago. Eldad 73247 Even at the end of the nineteenth century, sailors in the British Navy were not permitted to use knives and forks because using them was considered a sign of weakness. CM