What is the volume of a cube if each side measures 9 cm?
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Find the basis of vectors in ℝ³ for the plane passing through (1, 2, -1) and orthogonal to the vector (2, 1, 3).
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Math Question: Convert the mixed number 3 1/4 to an improper fraction. Then, find the prime factors of the resulting numerator, and simplify the fraction completely. (