Problem: The importance of infantry and light cavalry began to decline during the early Carolingian period, with a growing dominance of elite heavy cavalry. The use of militia-type levies of the free population declined over the Carolingian period. Although much of the Carolingian armies were mounted, a large proportion during the early period appear to have been mounted infantry, rather than true cavalry. One exception was Anglo-Saxon England, where the armies were still composed of regional levies, known as the fyrd, which were led by the local elites. In military technology, one of the main changes was the return of the crossbow, which had been known in Roman times and reappeared as a military weapon during the last part of the Early Middle Ages. Another change was the introduction of the stirrup, which increased the effectiveness of cavalry as shock troops. A technological advance that had implications beyond the military was the horseshoe, which allowed horses to be used in rocky terrain.
The importance of what military arm increased during the Carolingian era?
The answer is the following: heavy cavalry

Problem: During the 1930s, parts of the state began suffering the consequences of poor farming practices, extended drought and high winds. Known as the Dust Bowl, areas of Kansas, Texas, New Mexico and northwestern Oklahoma were hampered by long periods of little rainfall and abnormally high temperatures, sending thousands of farmers into poverty and forcing them to relocate to more fertile areas of the western United States. Over a twenty-year period ending in 1950, the state saw its only historical decline in population, dropping 6.9 percent as impoverished families migrated out of the state after the Dust Bowl.
What mistake led to the Dust Bowl?
The answer is the following: poor farming practices

Problem: In 1941, Reza Shah was forced to abdicate in favor of his son, Mohammad Reza Pahlavi, and established the Persian Corridor, a massive supply route that would last until the end of the ongoing war. The presence of so many foreign troops in the nation also culminated in the Soviet-backed establishment of two puppet regimes in the nation; the Azerbaijan People's Government, and the Republic of Mahabad. As the Soviet Union refused to relinquish the occupied Iranian territory, the Iran crisis of 1946 was followed, which particularly resulted in the dissolution of both puppet states, and the withdrawal of the Soviets.
What happened which ended in two puppet states dissolving and Soviet withdrawal out of Iran after WWII?
The answer is the following: the Iran crisis of 1946

Problem: The Information Office of the State Council of the PRC preserves an edict of the Zhengtong Emperor (r. 14351449) addressed to the Karmapa in 1445, written after the latter's agent had brought holy relics to the Ming court. Zhengtong had the following message delivered to the Great Treasure Prince of Dharma, the Karmapa:
Who maintains an edict of the Zhengtong Emperor?
The answer is the following:
The Information Office of the State Council of the PRC