The task is to generate the correct answer for a given math problem.
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Question: Problem: find the value of x : 2 x ² − 4 .

Answer: - 2,2


Question: Problem: a van takes 5 hours to cover a distance of 495 km . what speed in kph should the van maintain to cover the same distance in 3 / 2 of the previous time ?

Answer: 66


Question: Problem: if f ( x ) = 12 - x ^ 2 / 2 and f ( 2 k ) = 4 k , what is one possible value for k ?

Answer:
4