Given a question and a context passage, generate the answer having the word or phrase from the context passage. Here, the answer should be a shortest continous span from the passage.

Q: Context: Tove Strand was formerly married to Rune Gerhardsen, a fellow Labour Party politician and son of former Prime Minister Einar Gerhardsen whom she met in university. 
 Question: What is Tove Strand's spouse's name?

A: rune gerhardsen
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Q: Context: A solution is a mixture of two or more substances in which dissolved particles are distributed evenly throughout the solution. The substance that dissolves in a solution is called the solute, and the substance that does the dissolving is called the solvent. The concentration of a solution is the amount of solute in a given amount of solution. A solution with a lot of dissolved solute has a high concentration and is called a concentrated solution. A solution with little dissolved solute has a low concentration and is called a dilute solution. The concentration of a solution represents the percentage of the solution that is the solute. You can calculate the concentration of a solution using this formula: Concentration = Mass (or volume) of Solute Mass (or volume) of Solution 100% For example, if a 100-gram solution of salt water contains 3 grams of salt, then its concentration is: Concentration = 3g 100g 100% = 3% Q: A 1000 mL container of brand A juice drink contains 250 mL of juice and 750 mL of water. A 600 mL container of brand B juice drink contains 200 mL of juice and 400 mL of water. Which brand of juice drink is more concentrated, brand A or brand B? 250 mL 1000 mL 100% = 25% 200 mL 600 mL 100% = 33% A: Concentration(A) = Concentration(B) = You can conclude that brand B is more concentrated. 
 Question: a solution with a small amount of solute for a given amount of solution is called

A: dilute.
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Q: Context: To evaluate short- and mid-term level of imbalance after vestibular schwannoma (VS) microsurgery by the transpetrosal approach, to search for factors predictive of vestibular compensation, and to determine which patient categories need a postoperative vestibular rehabilitation program. Prospective cohort study at a tertiary referral center. Between 2010 and 2011, patients aged 18 to 75 operated on for VS by transpetrosal approaches were included. VS was characterized by its size (Koos classification) and the presence or not of a cystic component. Hearing was classified according to the Gardner Robertson grading. The preoperative workup included an audiogram, computerized video nystagmography (VNG) with caloric testing, gaze study, rotatory tests, click-evoked cervical vestibular evoked myogenic potential measurements (cVEMPs), and subjective visual vertical test. Patients were asked to complete a Dizziness Handicap Inventory (DHI). Postoperatively, patients were reevaluated on D7 (clinical status), D90 (VNG and DHI), and D180 (DHI). Timing and duration of vestibular rehabilitation were also recorded. Forty-eight patients were included. Preoperatively, 77% experienced mild instability problems with a mean DHI score of 14.1 (range 4-32). Postoperatively, 71% reported stable or even improved perceived stability. Mean DHI scores were 28.1 on D90 and 19.8 on D180. Serviceable hearing, cystic transformation, normal cVEMPs, diplopia, and vestibular syndrome on D7 were found to be predictive of worse equilibrium outcome than when absent. A preoperative caloric deficit greater than 75% seemed to be a good prognostic factor. Vestibular rehabilitation was conducted in 56% of patients. Starting it early (<1 mo) seemed to be beneficial for final equilibrium outcome. VS microsurgery provides good stability results. Some preoperative parameters may be predictive of worse or improved balance recovery, as is clinical status on D7. 
 Question: Which disease can be categorized using the Koos grading system?

A:
vestibular schwannoma
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