Problem: Nanjing is endowed with rich natural resources, which include more than 40 kinds of minerals. Among them, iron and sulfur reserves make up 40 percent of those of Jiangsu province. Its reserves of strontium rank first in East Asia and the South East Asia region. Nanjing also possesses abundant water resources, both from the Yangtze River and groundwater. In addition, it has several natural hot springs such as Tangshan Hot Spring in Jiangning and Tangquan Hot Spring in Pukou.
How many types of minerals are found in Nanjing?
The answer is the following: 40

Problem: Mexico's capital is both the oldest capital city in the Americas and one of two founded by Amerindians (Native Americans), the other being Quito. The city was originally built on an island of Lake Texcoco by the Aztecs in 1325 as Tenochtitlan, which was almost completely destroyed in the 1521 siege of Tenochtitlan, and subsequently redesigned and rebuilt in accordance with the Spanish urban standards. In 1524, the municipality of Mexico City was established, known as Mexico Tenochtitlan, and as of 1585 it was officially known as Ciudad de Mexico (Mexico City). Mexico City served as the political, administrative and financial center of a major part of the Spanish colonial empire. After independence from Spain was achieved, the Federal District was created in 1824.
What was the original name of Mexico City?
The answer is the following: Tenochtitlan

Problem: A virtual ISP (VISP) is an operation that purchases services from another ISP, sometimes called a wholesale ISP in this context, which allow the VISP's customers to access the Internet using services and infrastructure owned and operated by the wholesale ISP. VISPs resemble mobile virtual network operators and competitive local exchange carriers for voice communications.
What is a VISP?
The answer is the following: virtual ISP

Problem: The word phonology comes from the Greek , phone, "voice, sound," and the suffix -logy (which is from Greek , logos, "word, speech, subject of discussion"). Definitions of the term vary. Nikolai Trubetzkoy in Grundzuge der Phonologie (1939) defines phonology as "the study of sound pertaining to the system of language," as opposed to phonetics, which is "the study of sound pertaining to the act of speech" (the distinction between language and speech being basically Saussure's distinction between langue and parole). More recently, Lass (1998) writes that phonology refers broadly to the subdiscipline of linguistics concerned with the sounds of language, while in more narrow terms, "phonology proper is concerned with the function, behavior and organization of sounds as linguistic items." According to Clark et al. (2007), it means the systematic use of sound to encode meaning in any spoken human language, or the field of linguistics studying this use.
When did Lass write about phonology?
The answer is the following:
1998