Problem: Neptune is not visible to the unaided eye and is the only planet in the Solar System found by mathematical prediction rather than by empirical observation. Unexpected changes in the orbit of Uranus led Alexis Bouvard to deduce that its orbit was subject to gravitational perturbation by an unknown planet. Neptune was subsequently observed with a telescope on 23 September 1846 by Johann Galle within a degree of the position predicted by Urbain Le Verrier. Its largest moon, Triton, was discovered shortly thereafter, though none of the planet's remaining known 14 moons were located telescopically until the 20th century. The planet's distance from Earth gives it a very small apparent size, making it challenging to study with Earth-based telescopes. Neptune was visited by Voyager 2, when it flew by the planet on 25 August 1989. The advent of Hubble Space Telescope and large ground-based telescopes with adaptive optics has recently allowed for additional detailed observations from afar.
How was Neptune found?
The answer is the following: mathematical prediction

Problem: Victoria married her first cousin, Prince Albert of Saxe-Coburg and Gotha, in 1840. Their nine children married into royal and noble families across the continent, tying them together and earning her the sobriquet "the grandmother of Europe". After Albert's death in 1861, Victoria plunged into deep mourning and avoided public appearances. As a result of her seclusion, republicanism temporarily gained strength, but in the latter half of her reign her popularity recovered. Her Golden and Diamond Jubilees were times of public celebration.
Whatyear did Victoria marry Prince Albert?
The answer is the following: 1840

Problem: The birthplace of IBM, Endicott, suffered pollution for decades, however. IBM used liquid cleaning agents in circuit board assembly operation for more than two decades, and six spills and leaks were recorded, including one leak in 1979 of 4,100 gallons from an underground tank. These left behind volatile organic compounds in the town's soil and aquifer. Traces of volatile organic compounds have been identified in Endicott's drinking water, but the levels are within regulatory limits. Also, from 1980, IBM has pumped out 78,000 gallons of chemicals, including trichloroethane, freon, benzene and perchloroethene to the air and allegedly caused several cancer cases among the townspeople. IBM Endicott has been identified by the Department of Environmental Conservation as the major source of pollution, though traces of contaminants from a local dry cleaner and other polluters were also found. Remediation and testing are ongoing, however according to city officials, tests show that the water is safe to drink.
What location is the birthplace of IBM?
The answer is the following: Endicott

Problem: While the Umayyads and the Hashimites may have had bitterness between the two clans before Muhammad, the rivalry turned into a severe case of tribal animosity after the Battle of Badr. The battle saw three top leaders of the Umayyad clan (Utba ibn Rabi'ah, Walid ibn Utbah and Shaybah) killed by Hashimites (Ali, Hamza ibn 'Abd al-Muttalib and Ubaydah ibn al-Harith) in a three-on-three melee. This fueled the opposition of Abu Sufyan ibn Harb, the grandson of Umayya, to Muhammad and to Islam. Abu Sufyan sought to exterminate the adherents of the new religion by waging another battle with Muslims based in Medina only a year after the Battle of Badr. He did this to avenge the defeat at Badr. The Battle of Uhud is generally believed by scholars to be the first defeat for the Muslims, as they had incurred greater losses than the Meccans. After the battle, Abu Sufyan's wife Hind, who was also the daughter of Utba ibn Rabi'ah, is reported to have cut open the corpse of Hamza, taking out his liver which she then attempted to eat. Within five years after his defeat in the Battle of Uhud, however, Muhammad took control of Mecca and announced a general amnesty for all. Abu Sufyan and his wife Hind embraced Islam on the eve of the conquest of Mecca, as did their son (the future caliph Muawiyah I).
Who was the spouse of Abu Sufyan?
The answer is the following:
Hind