The problem: Answer a question about this article:
During the Permian all the Earth's major land masses, except portions of East Asia, were collected into a single supercontinent known as Pangaea. Pangaea straddled the equator and extended toward the poles, with a corresponding effect on ocean currents in the single great ocean (Panthalassa, the universal sea), and the Paleo-Tethys Ocean, a large ocean that was between Asia and Gondwana. The Cimmeria continent rifted away from Gondwana and drifted north to Laurasia, causing the Paleo-Tethys to shrink. A new ocean was growing on its southern end, the Tethys Ocean, an ocean that would dominate much of the Mesozoic Era. Large continental landmasses create climates with extreme variations of heat and cold ("continental climate") and monsoon conditions with highly seasonal rainfall patterns. Deserts seem to have been widespread on Pangaea.
During which period was the Tehtys Ocean dominant?
****
The answer: the Mesozoic Era

The problem: Answer a question about this article:
The ammunition and shells fired by these weapons are usually fitted with different types of fuses (barometric, time-delay, or proximity) to explode close to the airborne target, releasing a shower of fast metal fragments. For shorter-range work, a lighter weapon with a higher rate of fire is required, to increase a hit probability on a fast airborne target. Weapons between 20 mm and 40 mm caliber have been widely used in this role. Smaller weapons, typically .50 caliber or even 8 mm rifle caliber guns have been used in the smallest mounts.
What are two types of fuses used for shells?
****
The answer: barometric, time-delay, or proximity

The problem: Answer a question about this article:
Historians have divided the history of Cubism into phases. In one scheme, the first phase of Cubism, known as Analytic Cubism, a phrase coined by Juan Gris a posteriori, was both radical and influential as a short but highly significant art movement between 1910 and 1912 in France. A second phase, Synthetic Cubism, remained vital until around 1919, when the Surrealist movement gained popularity. English art historian Douglas Cooper proposed another scheme, describing three phases of Cubism in his book, The Cubist Epoch. According to Cooper there was "Early Cubism", (from 1906 to 1908) when the movement was initially developed in the studios of Picasso and Braque; the second phase being called "High Cubism", (from 1909 to 1914) during which time Juan Gris emerged as an important exponent (after 1911); and finally Cooper referred to "Late Cubism" (from 1914 to 1921) as the last phase of Cubism as a radical avant-garde movement. Douglas Cooper's restrictive use of these terms to distinguish the work of Braque, Picasso, Gris (from 1911) and Leger (to a lesser extent) implied an intentional value judgement.
What was the second phase of Cubism called?
****
The answer: Synthetic Cubism

The problem: Answer a question about this article:
It is believed that Nanjing was the largest city in the world from 1358 to 1425 with a population of 487,000 in 1400. Nanjing remained the capital of the Ming Empire until 1421, when the third emperor of the Ming dynasty, the Yongle Emperor, relocated the capital to Beijing.
Who was the third emperor of the Ming dynasty?
****
The answer:
the Yongle Emperor