Problem: The Han-era Chinese sailed in a variety of ships differing from those of previous eras, such as the tower ship. The junk design was developed and realized during Han. Junks featured a square-ended bow and stern, a flat-bottomed hull or carvel-shaped hull with no keel or sternpost, and solid transverse bulkheads in the place of structural ribs found in Western vessels. Moreover, Han ships were the first in the world to be steered using a rudder at the stern, in contrast to the simpler steering oar used for riverine transport, allowing them to sail on the high seas.
What type of boat design was first invented during the Han era?
The answer is the following: The junk design

Problem: Chopin has figured extensively in Polish literature, both in serious critical studies of his life and music and in fictional treatments. The earliest manifestation was probably an 1830 sonnet on Chopin by Leon Ulrich. French writers on Chopin (apart from Sand) have included Marcel Proust and Andre Gide; and he has also featured in works of Gottfried Benn and Boris Pasternak. There are numerous biographies of Chopin in English (see bibliography for some of these).
In addition to Polish and French, what other language has numerous biogrpahies of Chopin?
The answer is the following: English

Problem: A shipbuilding boom in the early part of the 20th century became massive during World War I, making Seattle somewhat of a company town; the subsequent retrenchment led to the Seattle General Strike of 1919, the first general strike in the country. A 1912 city development plan by Virgil Bogue went largely unused. Seattle was mildly prosperous in the 1920s but was particularly hard hit in the Great Depression, experiencing some of the country's harshest labor strife in that era. Violence during the Maritime Strike of 1934 cost Seattle much of its maritime traffic, which was rerouted to the Port of Los Angeles.
What was the first general labor strike in the 20th century?
The answer is the following: Seattle General Strike

Problem: Agrobacterium tumefaciens, a soil rhizosphere bacterium, can attach to plant cells and infect them with a callus-inducing Ti plasmid by horizontal gene transfer, causing a callus infection called crown gall disease. Schell and Van Montagu (1977) hypothesised that the Ti plasmid could be a natural vector for introducing the Nif gene responsible for nitrogen fixation in the root nodules of legumes and other plant species. Today, genetic modification of the Ti plasmid is one of the main techniques for introduction of transgenes to plants and the creation of genetically modified crops.
Who developed the procedures used in this transfer?
The answer is the following:
Schell and Van Montagu