What is the median of a set of 9 numbers, where the first 4 numbers are 10, 15, 20, and 25, and the remaining numbers form an arithmetic sequence with a common difference of 4?
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What is the horizontal asymptote of the function f(x) = 1/x?
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Math Question: What is the derivative of f(x) = 5x^4 - 2x^3 + 7x^2 - 9x + 3?