Problem: After World War II, eastern European countries such as the Soviet Union, Poland, Czechoslovakia, Hungary, Romania and Yugoslavia expelled the Germans from their territories. Many of those had inhabited these lands for centuries, developing a unique culture. Germans were also forced to leave the former eastern territories of Germany, which were annexed by Poland (Silesia, Pomerania, parts of Brandenburg and southern part of East Prussia) and the Soviet Union (northern part of East Prussia). Between 12 and 16,5 million ethnic Germans and German citizens were expelled westwards to allied-occupied Germany.
Approximately how many Germans were expelled from their home after world war II?
The answer is the following: 12 and 16,5 million ethnic Germans and German citizens

Problem: The city had surrendered without a fight to the invading Moors (Berbers and Arabs) by 714 AD, and the cathedral of Saint Vincent was turned into a mosque. Abd al-Rahman I, the first emir of Cordoba, ordered the city destroyed in 755 during his wars against other nobility, but several years later his son, Abdullah, had a form of autonomous rule over the province of Valencia. Among his administrative acts he ordered the building of a luxurious palace, the Russafa, on the outskirts of the city in the neighbourhood of the same name. So far no remains have been found. Also at this time Valencia received the name Medina al-Turab (City of Sand). When Islamic culture settled in, Valencia, then called Balansiyya, prospered from the 10th century, due to a booming trade in paper, silk, leather, ceramics, glass and silver-work. The architectural legacy of this period is abundant in Valencia and can still be appreciated today in the remnants of the old walls, the Baños del Almirante bath house, Portal de Valldigna street and even the Cathedral and the tower, El Micalet (El Miguelete), which was the minaret of the old mosque.
What feature of Valencia used to be a minaret?
The answer is the following: El Micalet

Problem: Until March 1, 2009, the Borough President of the Bronx was Adolfo Carrión Jr., elected as a Democrat in 2001 and 2005 before retiring early to direct the White House Office of Urban Affairs Policy. His successor, Democratic New York State Assembly member Rubén Díaz, Jr., who won a special election on April 21, 2009 by a vote of 86.3% (29,420) on the "Bronx Unity" line to 13.3% (4,646) for the Republican district leader Anthony Ribustello on the "People First" line, became Borough President on May 1.
When was Carrion Jr. re-elected Borough President?
The answer is the following: 2005

Problem: LEDs have also been used as a medium-quality voltage reference in electronic circuits. The forward voltage drop (e.g. about 1.7 V for a normal red LED) can be used instead of a Zener diode in low-voltage regulators. Red LEDs have the flattest I/V curve above the knee. Nitride-based LEDs have a fairly steep I/V curve and are useless for this purpose. Although LED forward voltage is far more current-dependent than a Zener diode, Zener diodes with breakdown voltages below 3 V are not widely available.
LED forward voltage is more current-dependent than what diode?
The answer is the following:
Zener