The correct answer is option D. "Companies replaced hand-operated brakes with air brakes on trains". The development of air brakes on trains was a significant improvement of railroad safety. Air brakes function much more faster than hand-operated brakes, because hand-operated brakes required that the brakemen turned the brakes in one car and jump to the next to set the brakes on, and so on.
D, hamartia is the correct answer. Hoped this helped (´ω｀★)
The correct answer to this question is Japan bombed the Pearl Harbor. The time when Japan bombed the Pearl Harbor got the United States to finally enter the war. Although the war has begun with the Germany's invasion of Poland, the United States agreed to stay out of it. However, everything changed on December 7, 1941, a date that every American will never forget.
The Harlem Renaissance took place at a time when European and white American writers and artists were particularly interested in African American artistic production, in part because of their interest in the “primitive.”<span>Modernist primitivism was a multifaceted phenomenon partly inspired by Freudian psychology, but it tended to extol so-called </span>“primitive”<span> peoples as enjoying a more direct and authentic relationship to the natural world and to simple human feeling than so-called </span>“over-civilized”<span> whites. They therefore were presumed by some to hold the key to the renovation of the arts. Early in the twentieth century, European avant-garde artists including Pablo Picasso (1881</span>–1974) had been inspired in part by African masks to break from earlier representational styles toward abstraction in painting and sculpture. The prestige of these revolutionary experiments caused African American intellectuals to look on African artistic traditions with new appreciation and to imagine new forms of self-representation, a desire reinforced by rising interest in black history. Black History Week, now Black History Month, was first celebrated in 1928 at the instigation of the historian Carter G. Woodson (1875–<span>1950).</span>
Although there was a plethora of factors preventing African Americans from advancing economically during the 1950s, the most significant was B.)<span> poor educational opportunities</span>.
