TASK DEFINITION: In this task, you are given a question and a context passage. You have to answer the question based on the given passage.
PROBLEM: Raiders can also be called?, Context: Perhaps the most famous raid by Oeselian pirates occurred in 1187, with the attack on the Swedish town of Sigtuna by Finnic raiders from Couronia and Oesel. Among the casualties of this raid was the Swedish archbishop Johannes. The city remained occupied for some time, contributing to its decline as a center of commerce in the 13th century and the rise of Uppsala, Visby, Kalmar and Stockholm. The Livonian Chronicle describes the Oeselians as using two kinds of ships, the piratica and the liburna. The former was a warship, the latter mainly a merchant ship. A piratica could carry approximately 30 men and had a high prow shaped like a dragon or a snakehead and a rectangular sail. Viking-age treasures from Estonia mostly contain silver coins and bars. Saaremaa has the richest finds of Viking treasures after Gotland in Sweden. This strongly suggests that Estonia was an important transit country during the Viking era.

SOLUTION: pirates

PROBLEM: What distinguishes the district of Houston?, Context: Houston was incorporated in 1837 under the ward system of representation. The ward designation is the progenitor of the eleven current-day geographically oriented Houston City Council districts. Locations in Houston are generally classified as either being inside or outside the Interstate 610 Loop. The inside encompasses the central business district and many residential neighborhoods that predate World War II. More recently, high-density residential areas have been developed within the loop. The city's outlying areas, suburbs and enclaves are located outside of the loop. Beltway 8 encircles the city another 5 miles (8.0 km) farther out.

SOLUTION: classified as either being inside or outside the Interstate 610 Loop

PROBLEM: What can copper form into?, Context: Chromobacterium violaceum and Pseudomonas fluorescens can both mobilize solid copper, as a cyanide compound. The ericoid mycorrhizal fungi associated with Calluna, Erica and Vaccinium can grow in copper metalliferous soils. The ectomycorrhizal fungus Suillus luteus protects young pine trees from copper toxicity. A sample of the fungus Aspergillus niger was found growing from gold mining solution; and was found to contain cyano metal complexes; such as gold, silver, copper iron and zinc. The fungus also plays a role in the solubilization of heavy metal sulfides.

SOLUTION:
cyanide compound