Problem: All police officers in the United Kingdom, whatever their actual rank, are 'constables' in terms of their legal position. This means that a newly appointed constable has the same arrest powers as a Chief Constable or Commissioner. However, certain higher ranks have additional powers to authorize certain aspects of police operations, such as a power to authorize a search of a suspect's house (section 18 PACE in England and Wales) by an officer of the rank of Inspector, or the power to authorize a suspect's detention beyond 24 hours by a Superintendent.
What can only Inspector-ranked UK officers do?
The answer is the following: authorize a search of a suspect's house

Problem: Antarctica continued to become more isolated and finally developed a permanent ice cap. Mountain building in western North America continued, and the Alps started to rise in Europe as the African plate continued to push north into the Eurasian plate, isolating the remnants of Tethys Sea. A brief marine incursion marks the early Oligocene in Europe. There appears to have been a land bridge in the early Oligocene between North America and Europe since the faunas of the two regions are very similar. During the Oligocene, South America was finally detached from Antarctica and drifted north toward North America. It also allowed the Antarctic Circumpolar Current to flow, rapidly cooling the continent.
During what period was there a land bridge joining Europe and North America?
The answer is the following: Oligocene

Problem: The First Opium War revealed the outdated state of the Chinese military. The Qing navy, composed entirely of wooden sailing junks, was severely outclassed by the modern tactics and firepower of the British Royal Navy. British soldiers, using advanced muskets and artillery, easily outmaneuvered and outgunned Qing forces in ground battles. The Qing surrender in 1842 marked a decisive, humiliating blow to China. The Treaty of Nanjing, the first of the unequal treaties, demanded war reparations, forced China to open up the five ports of Canton, Amoy, Fuchow, Ningpo and Shanghai to western trade and missionaries, and to cede Hong Kong Island to Britain. It revealed many inadequacies in the Qing government and provoked widespread rebellions against the already hugely unpopular regime.
What treaty marked the end of the First Opium War?
The answer is the following: Treaty of Nanjing,

Problem: An in-depth study of MP3 audio quality, sound artist and composer Ryan Maguire's project "The Ghost in the MP3" isolates the sounds lost during MP3 compression. In 2015, he released the track "moDernisT" (an anagram of "Tom's Diner"), composed exclusively from the sounds deleted during MP3 compression of the song "Tom's Diner", the track originally used in the formulation of the MP3 standard. A detailed account of the techniques used to isolate the sounds deleted during MP3 compression, along with the conceptual motivation for the project, was published in the 2014 Proceedings of the International Computer Music Conference.
Where was an account of the study published?
The answer is the following:
International Computer Music Conference