Problem: Eritrea:

During the last interglacial period, the Red Sea coast of Eritrea was occupied by early anatomically modern humans. It is believed that the area was on the route out of Africa that some scholars suggest was used by early humans to colonize the rest of the Old World. In 1999, the Eritrean Research Project Team composed of Eritrean, Canadian, American, Dutch and French scientists discovered a Paleolithic site with stone and obsidian tools dated to over 125,000 years old near the Bay of Zula south of Massawa, along the Red Sea littoral. The tools are believed to have been used by early humans to harvest marine resources like clams and oysters.

What did the research team find in Massawa?
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A: unanswerable

Problem: Bird migration:

Bird migration is not limited to birds that can fly. Most species of penguin (Spheniscidae) migrate by swimming. These routes can cover over 1,000 km (620 mi). Dusky grouse Dendragapus obscurus perform altitudinal migration mostly by walking. Emus Dromaius novaehollandiae in Australia have been observed to undertake long-distance movements on foot during droughts.

How do Emus migrate long distances during droughts?
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A: on foot

Problem: Punjab, Pakistan:

The onset of the southwest monsoon is anticipated to reach Punjab by May, but since the early 1970s the weather pattern has been irregular. The spring monsoon has either skipped over the area or has caused it to rain so hard that floods have resulted. June and July are oppressively hot. Although official estimates rarely place the temperature above 46 C, newspaper sources claim that it reaches 51 C and regularly carry reports about people who have succumbed to the heat. Heat records were broken in Multan in June 1993, when the mercury was reported to have risen to 54 C. In August the oppressive heat is punctuated by the rainy season, referred to as barsat, which brings relief in its wake. The hardest part of the summer is then over, but cooler weather does not come until late October.

The onset of what appears in October?
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A: unanswerable

Problem: Zhejiang:

Zhejiang, as the heartland of the Jiangnan (Yangtze River Delta), remained the wealthiest area during the Six Dynasties (220 or 222589), Sui, and Tang. After being incorporated into the Sui dynasty, its economic richness was used for the Sui dynasty's ambitions to expand north and south, particularly into Korea and Vietnam. The plan led the Sui dynasty to restore and expand the network which became the Grand Canal of China. The Canal regularly transported grains and resources from Zhejiang, through its metropolitan center Hangzhou (and its hinterland along both the Zhe River and the shores of Hangzhou Bay), and from Suzhou, and thence to the North China Plain. The debacle of the Korean war led to Sui's overthrow by the Tang, who then presided over a centuries-long golden age for the country. Zhejiang was an important economic center of the empire's Jiangnan East Circuit and was considered particularly prosperous. Throughout the Tang dynasty, The Grand Canal had remained effective, transporting grains and material resources to North China plain and metropolitan centers of the empire. As the Tang Dynasty disintegrated, Zhejiang constituted most of the territory of the regional kingdom of Wuyue.

Which dynasty restored and expanded the network that became the Grand Canal of China?
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A:
the Sui dynasty