Problem: Nanjing ( listen; Chinese: 南京, "Southern Capital") is the city situated in the heartland of lower Yangtze River region in China, which has long been a major centre of culture, education, research, politics, economy, transport networks and tourism. It is the capital city of Jiangsu province of People's Republic of China and the second largest city in East China, with a total population of 8,216,100, and legally the capital of Republic of China which lost the mainland during the civil war. The city whose name means "Southern Capital" has a prominent place in Chinese history and culture, having served as the capitals of various Chinese dynasties, kingdoms and republican governments dating from the 3rd century AD to 1949. Prior to the advent of pinyin romanization, Nanjing's city name was spelled as Nanking or Nankin. Nanjing has a number of other names, and some historical names are now used as names of districts of the city, and among them there is the name Jiangning (江寧), whose former character Jiang (江, River) is the former part of the name Jiangsu and latter character Ning (寧, simplified form 宁, Peace) is the short name of Nanjing. When being the capital of a state, for instance, ROC, Jing (京) is adopted as the abbreviation of Nanjing. Although as a city located in southern part of China becoming Chinese national capital as early as in Jin dynasty, the name Nanjing was designated to the city in Ming dynasty, about a thousand years later. Nanjing is particularly known as Jinling (金陵, literally meaning Gold Mountain) and the old name has been used since the Warring States Period in Zhou Dynasty.
What region is Nanjing in?
The answer is the following: lower Yangtze River region

Problem: Sport plays an important role in Estonian culture. After declaring independence from Russia in 1918, Estonia first competed as a nation at the 1920 Summer Olympics, although the National Olympic Committee was established in 1923. Estonian athletes took part of the Olympic Games until the country was annexed by the Soviet Union in 1940. The 1980 Summer Olympics Sailing regatta was held in the capital city Tallinn. After regaining independence in 1991, Estonia has participated in all Olympics. Estonia has won most of its medals in athletics, weightlifting, wrestling and cross-country skiing. Estonia has had very good success at the Olympic games given the country's small population. Estonia's best results were being ranked 13th in the medal table at the 1936 Summer Olympics, and 12th at the 2006 Winter Olympics.
What event did Estonia compete in as a nation for the first time ever?
The answer is the following: the 1920 Summer Olympics

Problem: Genes are regulated so that they are expressed only when the product is needed, since expression draws on limited resources.:7 A cell regulates its gene expression depending on its external environment (e.g. available nutrients, temperature and other stresses), its internal environment (e.g. cell division cycle, metabolism, infection status), and its specific role if in a multicellular organism. Gene expression can be regulated at any step: from transcriptional initiation, to RNA processing, to post-translational modification of the protein. The regulation of lactose metabolism genes in E. coli (lac operon) was the first such mechanism to be described in 1961.
When are genes expressed?
The answer is the following: only when the product is needed

Problem: Several scholars have suggested that the Prajñāpāramitā sūtras, which are among the earliest Mahāyāna sūtras, developed among the Mahāsāṃghika along the Kṛṣṇa River in the Āndhra region of South India.
The Prajnaparamita sutras were developed along the krsna river in what region of South India?
The answer is the following:
Āndhra