Problem: Brain:

Most of the space in the brain is taken up by axons, which are often bundled together in what are called nerve fiber tracts. A myelinated axon is wrapped in a fatty insulating sheath of myelin, which serves to greatly increase the speed of signal propagation. (There are also unmyelinated axons). Myelin is white, making parts of the brain filled exclusively with nerve fibers appear as light-colored white matter, in contrast to the darker-colored grey matter that marks areas with high densities of neuron cell bodies.

An axon that can greatly increase speed of signals is wrapped in what?
---
A: sheath of myelin

Problem: Buckingham Palace:

In the Middle Ages, the site of the future palace formed part of the Manor of Ebury (also called Eia). The marshy ground was watered by the river Tyburn, which still flows below the courtyard and south wing of the palace. Where the river was fordable (at Cow Ford), the village of Eye Cross grew. Ownership of the site changed hands many times; owners included Edward the Confessor and his queen consort Edith of Wessex in late Saxon times, and, after the Norman Conquest, William the Conqueror. William gave the site to Geoffrey de Mandeville, who bequeathed it to the monks of Westminster Abbey.

Who did William the Conqueror give the site of the palace to?
---
A: Geoffrey de Mandeville

Problem: Tajikistan:

Tajikistan (i/tdikstn/, /tdikstn/, or /tdikistn/; Persian: [tdikstn]), officially the Republic of Tajikistan (Persian: Tajik: , Cumhuriji Tocikiston/Jumhuriyi Tojikiston; Russian: , Respublika Tadzhikistan), is a mountainous, landlocked country in Central Asia with an estimated 8 million people in 2013, and an area of 143,100 km2 (55,300 sq mi). It is bordered by Afghanistan to the south, Uzbekistan to the west, Kyrgyzstan to the north, and China to the east. Pakistan lies to the south, separated by the narrow Wakhan Corridor. Traditional homelands of Tajik people included present-day Tajikistan, Afghanistan and Uzbekistan.

What country lies to Tajikistans east?
---
A: China

Problem: Genocide:

Highlighting the potential for state and non-state actors to commit genocide in the 21st century, for example, in failed states or as non-state actors acquire weapons of mass destruction, Adrian Gallagher defined genocide as 'When a source of collective power (usually a state) intentionally uses its power base to implement a process of destruction in order to destroy a group (as defined by the perpetrator), in whole or in substantial part, dependent upon relative group size'. The definition upholds the centrality of intent, the multidimensional understanding of destroy, broadens the definition of group identity beyond that of the 1948 definition yet argues that a substantial part of a group has to be destroyed before it can be classified as genocide (dependent on relative group size).

The centrality of what does Gallagher's definition uphold?
---
A:
unanswerable