Problem: The Chronicle provides a mythic tale of Oleg's death. A sorcerer prophesies that the death of the Grand Prince would be associated with a certain horse. Oleg has the horse sequestered, and it later dies. Oleg goes to visit the horse and stands over the carcass, gloating that he had outlived the threat, when a snake strikes him from among the bones, and he soon becomes ill and dies. The Chronicle reports that Prince Igor succeeded Oleg in 913, and after some brief conflicts with the Drevlians and the Pechenegs, a period of peace ensued for over twenty years.
What known document tells of the death of Oleg?
The answer is the following: The Chronicle

Problem: The prevalence of HIV-infection among the adult population is 1.8%. Only 20% of infected pregnant women receive anti retroviral coverage to prevent transmission to newborns.
What percentage of the adult population has an HIV-infection?
The answer is the following: 1.8%

Problem: Whitehall's disquiet at the failures of the RAF led to the replacement of Dowding (who was already due for retirement) with Sholto Douglas on 25 November. Douglas set about introducing more squadrons and dispersing the few GL sets to create a carpet effect in the southern counties. Still, in February 1941, there remained only seven squadrons with 87 pilots, under half the required strength. The GL carpet was supported by six GCI sets controlling radar-equipped night-fighters. By the height of the Blitz, they were becoming more successful. The number of contacts and combats rose in 1941, from 44 and two in 48 sorties in January 1941, to 204 and 74 in May (643 sorties). But even in May, 67% of the sorties were visual cat's-eye missions. Curiously, while 43% of the contacts in May 1941 were by visual sightings, they accounted for 61% of the combats. Yet when compared with Luftwaffe daylight operations, there was a sharp decline in German losses to 1%. If a vigilant bomber crew could spot the fighter first, they had a decent chance at evading it.
What supported the GL carpet?
The answer is the following: six GCI sets controlling radar-equipped night-fighters

Problem: The islands are located about halfway between Hawaii and Australia, north of Nauru and Kiribati, east of the Federated States of Micronesia, and south of the U.S. territory of Wake Island, to which it lays claim. The atolls and islands form two groups: the Ratak (sunrise) and the Ralik (sunset). The two island chains lie approximately parallel to one another, running northwest to southeast, comprising about 750,000 square miles (1,900,000 km2) of ocean but only about 70 square miles (180 km2) of land mass. Each includes 15 to 18 islands and atolls. The country consists of a total of 29 atolls and five isolated islands.
What nation lies to the west of the Marshall Islands?
The answer is the following:
the Federated States of Micronesia