In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

Input: Consider Input: The expansion of what further cemented Houston's emergence as a powerhouse commercial city?, Context: By 1860, Houston had emerged as a commercial and railroad hub for the export of cotton. Railroad spurs from the Texas inland converged in Houston, where they met rail lines to the ports of Galveston and Beaumont. During the American Civil War, Houston served as a headquarters for General John Bankhead Magruder, who used the city as an organization point for the Battle of Galveston. After the Civil War, Houston businessmen initiated efforts to widen the city's extensive system of bayous so the city could accept more commerce between downtown and the nearby port of Galveston. By 1890, Houston was the railroad center of Texas.

Output: bayous


Input: Consider Input: What economic improvement did the successors make?, Context: Louis-Philippe was overthrown by a popular uprising in the streets of Paris in 1848. His successor, Napoleon III, and the newly appointed prefect of the Seine, Georges-Eugène Haussmann, launched a gigantic public works project to build wide new boulevards, a new opera house, a central market, new aqueducts, sewers, and parks, including the Bois de Boulogne and Bois de Vincennes. In 1860, Napoleon III also annexed the surrounding towns and created eight new arrondissements, expanding Paris to its current limits.

Output: central market


Input: Consider Input: What metal is used?, Context: The Faraday constant F is the charge of one mole of electrons, equal to the Avogadro constant NA multiplied by the elementary charge e. It can be determined by careful electrolysis experiments, measuring the amount of silver dissolved from an electrode in a given time and for a given electric current. In practice, it is measured in conventional electrical units, and so given the symbol F90. Substituting the definitions of NA and e, and converting from conventional electrical units to SI units, gives the relation to the Planck constant.
Output: silver