Problem: The first half of the 20th century in Russia and the Soviet Union was marked by a succession of wars, famines and other disasters, each accompanied by large-scale population losses. Stephen J. Lee estimates that, by the end of World War II in 1945, the Russian population was about 90 million fewer than it could have been otherwise.
When was the Russian population estimated to be about 90 million fewer than it could have been?
The answer is the following: 1945

Problem: On May 12, 2009, China marked the first anniversary of the quake with a moment of silence as people across the nation remembered the dead. The government also opened access to the sealed ruins of the Beichuan county seat for three days, after which it will be frozen in time as a state earthquake relic museum, to remind people of the terrible disaster. There were also several concerts across the country to raise money for the survivors of the quake.
What is the Beichuan museum meant to remind people of?
The answer is the following: the terrible disaster

Problem: Iran has an area of 1,648,195 km2 (636,372 sq mi). Iran lies between latitudes 24° and 40° N, and longitudes 44° and 64° E. Its borders are with Azerbaijan (611 km or 380 mi, with Azerbaijan-Naxcivan exclave, 179 km or 111 mi) and Armenia (35 km or 22 mi) to the north-west; the Caspian Sea to the north; Turkmenistan (992 km or 616 mi) to the north-east; Pakistan (909 km or 565 mi) and Afghanistan (936 km or 582 mi) to the east; Turkey (499 km or 310 mi) and Iraq (1,458 km or 906 mi) to the west; and finally the waters of the Persian Gulf and the Gulf of Oman to the south.
What longitudes does Iran lie between?
The answer is the following: 44° and 64° E

Problem: By the Middle Ages, large numbers of Jews lived in the Holy Roman Empire and had assimilated into German culture, including many Jews who had previously assimilated into French culture and had spoken a mixed Judeo-French language. Upon assimilating into German culture, the Jewish German peoples incorporated major parts of the German language and elements of other European languages into a mixed language known as Yiddish. However tolerance and assimilation of Jews in German society suddenly ended during the Crusades with many Jews being forcefully expelled from Germany and Western Yiddish disappeared as a language in Germany over the centuries, with German Jewish people fully adopting the German language.
What language did the Jews speak prior to assimilating into German culture?
The answer is the following:
Judeo-French