Problem: Nanjing:

During the period of NorthSouth division, Nanjing remained the capital of the Southern dynasties for more than two and a half centuries. During this time, Nanjing was the international hub of East Asia. Based on historical documents, the city had 280,000 registered households. Assuming an average Nanjing household had about 5.1 people at that time, the city had more than 1.4 million residents.

What is the estimated population of Nanjing during that time?
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A: more than 1.4 million residents

Problem: Swaziland:

The considerable spending did not lead to more growth and did not benefit the poor. Much of the increased spending has gone to current expenditures related to wages, transfers, and subsidies. The wage bill today constitutes over 15% of GDP and 55% of total public spending; these are some of the highest levels on the African continent. The recent rapid growth in SACU revenues has, however, reversed the fiscal situation, and a sizeable surplus was recorded since 2006. SACU revenues today account for over 60% of total government revenues. On the positive side, the external debt burden has declined markedly over the last 20 years, and domestic debt is almost negligible; external debt as a percent of GDP was less than 20% in 2006.

What makes up 15% of total public spending?
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A: unanswerable

Problem: Solar energy:

Solar concentrating technologies such as parabolic dish, trough and Scheffler reflectors can provide process heat for commercial and industrial applications. The first commercial system was the Solar Total Energy Project (STEP) in Shenandoah, Georgia, USA where a field of 114 parabolic dishes provided 50% of the process heating, air conditioning and electrical requirements for a clothing factory. This grid-connected cogeneration system provided 400 kW of electricity plus thermal energy in the form of 401 kW steam and 468 kW chilled water, and had a one-hour peak load thermal storage. Evaporation ponds are shallow pools that concentrate dissolved solids through evaporation. The use of evaporation ponds to obtain salt from sea water is one of the oldest applications of solar energy. Modern uses include concentrating brine solutions used in leach mining and removing dissolved solids from waste streams. Clothes lines, clotheshorses, and clothes racks dry clothes through evaporation by wind and sunlight without consuming electricity or gas. In some states of the United States legislation protects the "right to dry" clothes. Unglazed transpired collectors (UTC) are perforated sun-facing walls used for preheating ventilation air. UTCs can raise the incoming air temperature up to 22 C (40 F) and deliver outlet temperatures of 4560 C (113140 F). The short payback period of transpired collectors (3 to 12 years) makes them a more cost-effective alternative than glazed collection systems. As of 2003, over 80 systems with a combined collector area of 35,000 square metres (380,000 sq ft) had been installed worldwide, including an 860 m2 (9,300 sq ft) collector in Costa Rica used for drying coffee beans and a 1,300 m2 (14,000 sq ft) collector in Coimbatore, India, used for drying marigolds.

What is one of the oldest uses of solar energy?
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A: use of evaporation ponds to obtain salt from sea water

Problem: Beer:

The word ale comes from Old English ealu (plural ealo), in turn from Proto-Germanic *alu (plural *alu), ultimately from the Proto-Indo-European base *helut-, which holds connotations of "sorcery, magic, possession, intoxication". The word beer comes from Old English beor, from Proto-Germanic *beuza, probably from Proto-Indo-European *beusom, originally "brewer's yeast, beer dregs", although other theories have been provided connecting the word with Old English beow, "barley", or Latin bibere, "to drink". On the currency of two words for the same thing in the Germanic languages, the 12th-century Old Icelandic poem Alvissmal says, "Ale it is called among men, but among the gods, beer."

What is the plural of the word ale?
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A:
unanswerable