Math question: In a set, the median is the average of the two middle terms. If the median of a set is 10 and there are 5 terms, what are the possibilities for the two middle terms?
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What is the essential condition that signifies the equality of triangles?
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Math question: Find the fourth-order derivative of f(x) = 3x^4 - 2x^2 + 5x - 1.