Due to a wealth of fossil remains, the first of which was found in the late 1870s, Diplodocus is one of the best-studied dinosaurs. The herbivorous dinosaur roamed western North America about 145 million years ago, during the late Jurassic period, walked on four legs, and had an extremely small brain and skull. One of the longest known sauropods, Diplodocus could grow to be 88 ft (27 m) long, most of which was neck and tail. With what man-made structure is it often compared? Discuss
Source: The Free Dictionary
British statesman Harold Macmillan held several government posts during World War II, including minister resident in North Africa. After serving in several other positions, he became prime minister in 1957. Macmillan accelerated Britain’s decolonization, especially in Africa. In a memorable speech to the South African parliament in 1960, he said a “wind of change” was sweeping across Africa, which was experiencing a growth in national consciousness. What were the reactions to the speech? 
The celebration of winter that has been held since the mid-1950s in 
Rockwell was an American illustrator whose idealized scenes of family life in small-town America gained enormous popularity with the public. His illustrations appeared in major periodicals such as Collier’s and Life. From 1916 to 1963, he produced 317 covers for The Saturday Evening Post, and during WWII his patriotic posters were distributed by the government. What unusually serious subject did the sentimental illustrator cover for Look magazine later in his career? 
Street art is any art developed in public spaces and includes traditional graffiti, stencil graffiti, sticker art, video projections, street installations, and posters. Though it usually refers to art of an illicit nature, the term is used to distinguish contemporary public-space artwork from territorial graffiti, vandalism, and corporate art. Some street artists have even achieved mainstream recognition and commercial success. Who are some prominent street artists? 
In 1925, a diphtheria outbreak threatened the city of Nome. The town’s supply of antitoxin had run out, and a mail shipment would have taken weeks to arrive. After learning of the crisis, 20 mushers and some 150 sled dogs, including the famous Balto, relayed fresh antitoxin 674 miles (1,085 km) in a record five and a half days, preventing an epidemic. Today, the heroic journey is commemorated by the annual Iditarod Trail Sled Dog Race. How long did a reenactment of the serum run take in 1975?