Problem: Stockton and Kearny went on to recover Los Angeles and force the capitulation of Alta California with the "Treaty of Cahuenga" on January 13, 1847. As a result of the Mexican–American War of 1846–48, the territory of Alta California, including San Diego, was ceded to the United States by Mexico, under the terms of the Treaty of Guadalupe Hidalgo in 1848. The Mexican negotiators of that treaty tried to retain San Diego as part of Mexico, but the Americans insisted that San Diego was "for every commercial purpose of nearly equal importance to us with that of San Francisco," and the Mexican-American border was eventually established to be one league south of the southernmost point of San Diego Bay, so as to include the entire bay within the United States.
Why was the border between Mexico and the United States established one league south of San Diego Bay's most southern tip?
The answer is the following: to include the entire bay within the United States

Problem: Classical India refers to the period when much of the Indian subcontinent was reunited under the Gupta Empire (c. 320–550 CE). This period has been called the Golden Age of India and was marked by extensive achievements in science, technology, engineering, art, dialectic, literature, logic, mathematics, astronomy, religion, and philosophy that crystallized the elements of what is generally known as Hindu culture. The Hindu-Arabic numerals, a positional numeral system, originated in India and was later transmitted to the West through the Arabs. Early Hindu numerals had only nine symbols, until 600 to 800 CE, when a symbol for zero was developed for the numeral system. The peace and prosperity created under leadership of Guptas enabled the pursuit of scientific and artistic endeavors in India.
What philosophy  formed at the time of the Gupta Empire?
The answer is the following: Hindu culture

Problem: During fiscal year 2007, $537.5 million was received in total research support, including $444 million in federal obligations. The University has over 150 National Institutes of Health funded inventions, with many of them licensed to private companies. Governmental agencies and non-profit foundations such as the NIH, United States Department of Defense, National Science Foundation, and NASA provide the majority of research grant funding, with Washington University being one of the top recipients in NIH grants from year-to-year. Nearly 80% of NIH grants to institutions in the state of Missouri went to Washington University alone in 2007. Washington University and its Medical School play a large part in the Human Genome Project, where it contributes approximately 25% of the finished sequence. The Genome Sequencing Center has decoded the genome of many animals, plants, and cellular organisms, including the platypus, chimpanzee, cat, and corn.
What  are some organisms for which  the Genome Sequencing Center at  Washington University Medical provided genome decoding?
The answer is the following: platypus, chimpanzee, cat, and corn

Problem: In recent years, Nanjing has been developing its economy, commerce, industry, as well as city construction. In 2013 the city's GDP was RMB 801 billion (3rd in Jiangsu), and GDP per capita(current price) was RMB 98,174(US$16041), a 11 percent increase from 2012. The average urban resident's disposable income was RMB 36,200, while the average rural resident's net income was RMB 14,513. The registered urban unemployment rate was 3.02 percent, lower than the national average (4.3 percent). Nanjing's Gross Domestic Product ranked 12th in 2013 in China, and its overall competence ranked 6th in mainland and 8th including Taiwan and Hong Kong in 2009.
What was Nanjing's GDP per person in 2013?
The answer is the following:
RMB 98,174(US$16041)