Problem: A series of experiments performed from the late 1800s to the early 1900s revealed that diabetes is caused by the absence of a substance normally produced by the pancreas. In 1869, Oskar Minkowski and Joseph von Mering found that diabetes could be induced in dogs by surgical removal of the pancreas. In 1921, Canadian professor Frederick Banting and his student Charles Best repeated this study, and found that injections of pancreatic extract reversed the symptoms produced by pancreas removal. Soon, the extract was demonstrated to work in people, but development of insulin therapy as a routine medical procedure was delayed by difficulties in producing the material in sufficient quantity and with reproducible purity. The researchers sought assistance from industrial collaborators at Eli Lilly and Co. based on the company's experience with large scale purification of biological materials. Chemist George Walden of Eli Lilly and Company found that careful adjustment of the pH of the extract allowed a relatively pure grade of insulin to be produced. Under pressure from Toronto University and a potential patent challenge by academic scientists who had independently developed a similar purification method, an agreement was reached for non-exclusive production of insulin by multiple companies. Prior to the discovery and widespread availability of insulin therapy the life expectancy of diabetics was only a few months.
What could be adjusted in a sample of pancreatic extract to produce purer insulin?
The answer is the following: pH

Problem: The Premier League sends representatives to UEFA's European Club Association, the number of clubs and the clubs themselves chosen according to UEFA coefficients. For the 201213 season the Premier League has 10 representatives in the Association: Arsenal, Aston Villa, Chelsea, Everton, Fulham, Liverpool, Manchester City, Manchester United, Newcastle United and Tottenham Hotspur. The European Club Association is responsible for electing three members to UEFA's Club Competitions Committee, which is involved in the operations of UEFA competitions such as the Champions League and UEFA Europa League.
How many members is the European Club Association responsible for electing to the UEFA Club Competitions Committee?
The answer is the following: three

Problem: With Japanese and Allied forces occupying various parts of the island, over the following six months both sides poured resources into an escalating battle of attrition on land, at sea, and in the sky. Most of the Japanese aircraft based in the South Pacific were redeployed to the defense of Guadalcanal. Many were lost in numerous engagements with the Allied air forces based at Henderson Field as well as carrier based aircraft. Meanwhile, Japanese ground forces launched repeated attacks on heavily defended US positions around Henderson Field, in which they suffered appalling casualties. To sustain these offensives, resupply was carried out by Japanese convoys, termed the "Tokyo Express" by the Allies. The convoys often faced night battles with enemy naval forces in which they expended destroyers that the IJN could ill-afford to lose. Later fleet battles involving heavier ships and even daytime carrier battles resulted in a stretch of water near Guadalcanal becoming known as "Ironbottom Sound" from the multitude of ships sunk on both sides. However, the Allies were much better able to replace these losses. Finally recognizing that the campaign to recapture Henderson Field and secure Guadalcanal had simply become too costly to continue, the Japanese evacuated the island and withdrew in February 1943. In the sixth month war of attrition, the Japanese had lost as a result of failing to commit enough forces in sufficient time.
Where were most of the Japanese aircraft in the South Pacific redeployed to defend?
The answer is the following: Guadalcanal

Problem: Vladimir had been prince of Novgorod when his father Sviatoslav I died in 972. He was forced to flee to Scandinavia in 976 after his half-brother Yaropolk had murdered his other brother Oleg and taken control of Rus. In Scandinavia, with the help of his relative Earl Hakon Sigurdsson, ruler of Norway, Vladimir assembled a Viking army and reconquered Novgorod and Kiev from Yaropolk. As Prince of Kiev, Vladimir's most notable achievement was the Christianization of Kievan Rus', a process that began in 988. The Primary Chronicle states that when Vladimir had decided to accept a new faith instead of the traditional idol-worship (paganism) of the Slavs, he sent out some of his most valued advisors and warriors as emissaries to different parts of Europe. They visited the Christians of the Latin Rite, the Jews, and the Muslims before finally arriving in Constantinople. They rejected Islam because, among other things, it prohibited the consumption of alcohol, and Judaism because the god of the Jews had permitted his chosen people to be deprived of their country. They found the ceremonies in the Roman church to be dull. But at Constantinople, they were so astounded by the beauty of the cathedral of Hagia Sophia and the liturgical service held there that they made up their minds there and then about the faith they would like to follow. Upon their arrival home, they convinced Vladimir that the faith of the Byzantine Rite was the best choice of all, upon which Vladimir made a journey to Constantinople and arranged to marry Princess Anna, the sister of Byzantine emperor Basil II.
When did the Christianization of Kievan begin?
The answer is the following:
988